Technology map of European quantum projects

What each quantum technology needs, from the platform down to its subsystems, components and materials, with the EU-funded projects and companies working on each part, the materials on the EU list of critical raw materials and the quantum patents read from EPO Open Patent Services. Choose a platform, then select a part to see what it is and where the information comes from.

A reference structure of what each quantum technology needs, down to materials, compiled from public review articles and EU law. It is not a supplier assessment, not a complete bill of materials and not an assessment of any company or country. Each part is sourced to a passage in a review article; project and company figures are keyword matches on CORDIS project titles. Pending review by a domain expert before promotion. Compiled 2026-10-25.

Technology atlas of Trapped ions on the technology hub The value chain with its documented European actors and evidence gaps, facilities, funding, standards and policy measures on one page.

Trapped ions: 21 parts (4 subsystems, 11 components and 6 materials), 3 of them critical raw materials; for 19 of the parts, no EU-funded project title names them.

EU activity: the EU-funded projects whose title names the part or one of its parts. Larger circles mean more projects.

None: no project
Low: 1 to 4 projects
Medium: 5 to 19 projects
High: 20 or more projects
Critical raw material (Regulation (EU) 2024/1252, Annex II)
Also a strategic raw material (Annex I)

Select a part in the tree, or use Tab and Enter, to see what it is, its sources, its EU-funded projects and its companies. Escape clears the selection.

Method and caveats

Parts: each platform is broken down into subsystems, components and materials named in a review article or an official document, and every part cites the passage (section, figure or paragraph) that places it in its parent. Descriptions are in our own words. This is a reference structure from public literature, not a complete bill of materials and not a supplier assessment, and it is pending review by a domain expert.
EU activity: a part counts the EU-funded quantum projects of the CORDIS snapshot whose title contains one of its keywords (case-insensitive whole words; * stands for any ending), together with the projects of its own parts, so a parent counts the union of its own and its children's projects. Most parts have generic keywords, so the title must also name the platform; parts with specific keywords, such as dilution refrigerators or nanowire detectors, count any quantum project. Titles rarely name components or materials, so "none" means that no project title names the part, not that nobody in Europe works on it.
Companies are the organisations that CORDIS records as private for-profit entities (activity type PRC) taking part in those projects; SMEs are those CORDIS flags as SMEs. Taking part in a project does not mean supplying the part.
Critical raw materials: a material is marked CRM when it is, or is made of, a raw material listed in Annex II of Regulation (EU) 2024/1252, and SRM when the entry is also a strategic raw material in Annex I; each part names its Annex entry and point. Materials whose link to an entry needs expert judgement, such as sapphire (crystalline aluminium oxide), barium (the Annexes list baryte) and KTP, are not marked and say why.
Ownership: for the companies matched to a Legal Entity Identifier by the background lookups of the supply-chain page, GLEIF reports whether their ultimate parent, or direct parent when no ultimate parent is reported, has its legal address outside the EU. This describes reported consolidation, not control or risk.
Patents: distinct quantum patent families (EPO Open Patent Services, CPC groups G06N10, H04L9/0852, H04B10/70) of the companies of a part, from the background lookups of the supply-chain page; when a company has more publications than were read, the count is a lower bound. Patent classes are not yet matched to individual parts.

Source of project data: CORDIS, Publications Office of the European Union, reused under the European Commission reuse notice (Decision 2011/833/EU). No endorsement by the sources is implied.

All parts as text

Every platform with each of its parts, their figures and their sources. The platform shown above is open.

Superconducting circuits (28 parts)

Superconducting circuits
Platform · Superconducting circuits
Qubits built from superconducting electrical circuits on a chip, controlled and read out with microwave signals at millikelvin temperatures.
40 EU-funded projects · 86 organisations · 22 companies (17 SMEs) · 19 countries · EU activity: high
31 of these projects name the part itself; the others come from its parts.
Companies in the most of these projects
1. Bluefors OY (FI): 2 projects, SME
2. Eurice European Research and Project Office GMBH (DE): 2 projects, SME
3. Low Noise Factory AB (SE): 2 projects, SME
4. Orange Quantum Systems Operational BV (NL): 2 projects, SME
5. Quantware B.v. (NL): 2 projects, SME
Ownership (GLEIF): 22 of 22 companies checked; 0 of the 7 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 178, from 22 companies checked.
Title keywords: superconducting qubit*, superconducting quantum, superconducting circuit*, superconducting processor*, transmon*, fluxonium*, josephson*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G06N10/40.
Sources
- A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. I (Introduction) and Sec. II (Engineering quantum circuits).
- Dilution refrigerator
  Subsystem · Superconducting circuits › Dilution refrigerator
  The cryostat that keeps the processor below about 20 mK, cooling it by mixing two helium isotopes.
  8 EU-funded projects · 17 organisations · 5 companies (3 SMEs) · 9 countries · EU activity: medium
  Companies in the most of these projects
  1. Equal 1 Laboratories Ireland Limited (IE): 1 project, SME
  2. IBM Research GMBH (CH): 1 project
  3. Kiutra GMBH (DE): 1 project, SME
  4. Scientific Cryo Systems Ug (DE): 1 project
  5. Semiqon Technologies OY (FI): 1 project, SME
  Ownership (GLEIF): 5 of 5 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 11, from 5 companies checked.
  Title keywords: cryogenic*, cryostat*, millikelvin, sub-kelvin, cryo-cmos, cryo-electronic*.
  Sources
  - Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Abstract and Introduction, first paragraph.
  - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.1 (Dilution refrigerator).
  - Dilution unit and mixing chamber
    Component · Superconducting circuits › Dilution refrigerator › Dilution unit and mixing chamber
    The coldest stage, where helium-3 crosses from a concentrated into a dilute phase in helium-4 and absorbs heat.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: dilution refrigerat*, dilution unit*, dilution cryostat*, mixing chamber*.
    CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: F25B9/12.
    Sources
    - Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Introduction, first paragraph (mixing of the isotopes); paragraph on mixing chamber size.
    - Helium-3 and helium-4 mixture CRM
      Material · Superconducting circuits › Dilution refrigerator › Dilution unit and mixing chamber › Helium-3 and helium-4 mixture
      The working fluid of the dilution unit, a mixture of the helium-3 and helium-4 isotopes.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: helium, Annex II point (p). Annex II lists helium without distinguishing its isotopes.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: helium-3, 3he, helium isotope*.
      Sources
      Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Introduction, first paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (p).
  - Pulse-tube cryocooler
    Component · Superconducting circuits › Dilution refrigerator › Pulse-tube cryocooler
    A closed-cycle cooler that precools the cryostat stages without a bath of liquid helium.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: pulse tube*, pulse-tube*, cryocooler*, cryo-cooler*.
    CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: F25B9/145.
    Sources
    - Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Introduction, second paragraph (closed cycle refrigerators).
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.1 (two pulse tube coolers at the 50K and 4K stages).
  - Radiation and magnetic shielding
    Component · Superconducting circuits › Dilution refrigerator › Radiation and magnetic shielding
    Infrared-blocking filters, absorbing material and magnetic shields that keep stray radiation and fields away from the qubits.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: infrared filter*, magnetic shield*, radiation shield*, shielding; counted only when the title also names the platform.
    Sources
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 1.1 (Typical cabling).
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. III E 4 (Cryogenic engineering).
- Qubit chip
  Subsystem · Superconducting circuits › Qubit chip
  Superconducting circuits patterned on a crystalline substrate, with Josephson junctions as their non-linear element.
  12 EU-funded projects · 23 organisations · 2 companies (2 SMEs) · 11 countries · EU activity: medium
  Companies in the most of these projects
  1. Silent Waves (FR): 1 project, SME
  2. Zurich Instruments AG (CH): 1 project, SME
  Ownership (GLEIF): 2 of 2 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 4, from 2 companies checked.
  Title keywords: quantum chip*, qubit chip*, quantum processor*, qubit*, fabricat*; counted only when the title also names the platform.
  Sources
  - Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 3 (Participation), Sec. 4 (Metallization) and Sec. 5 (Tunneling barriers).
  - Josephson junctions
    Component · Superconducting circuits › Qubit chip › Josephson junctions
    Thin oxide barriers between superconducting leads that give each qubit its loss-free non-linear inductance.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: josephson junction*, tunnel junction*, tunnelling barrier*, tunneling barrier*.
    CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: H10N60/12.
    Sources
    - Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 5.1 (Composition).
    - Aluminium and aluminium oxide CRM SRM
      Material · Superconducting circuits › Qubit chip › Josephson junctions › Aluminium and aluminium oxide
      The most common junction is an aluminium oxide barrier between aluminium leads.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: bauxite/alumina/aluminium, Annex II point (c). Also a strategic raw material: bauxite/alumina/aluminium, Annex I point (a).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: aluminium, aluminum, alumina, aluminium oxide, aluminum oxide; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 5.1 (Composition), second paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (c); Annex I, Section 1, point (a).
  - Superconducting metal films
    Component · Superconducting circuits › Qubit chip › Superconducting metal films
    Thin films that form the qubit capacitors, resonators, inductors, wiring and ground planes.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: superconducting film*, thin film*, metallisation, metallization; counted only when the title also names the platform.
    Sources
    - Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 4 (Metallization) and Sec. 4.1 (Composition).
    - Aluminium CRM SRM
      Material · Superconducting circuits › Qubit chip › Superconducting metal films › Aluminium
      The most widely used film metal in superconducting quantum circuits.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: bauxite/alumina/aluminium, Annex II point (c). Also a strategic raw material: bauxite/alumina/aluminium, Annex I point (a).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: aluminium, aluminum; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 4.1 (Composition), first paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (c); Annex I, Section 1, point (a).
    - Niobium CRM
      Material · Superconducting circuits › Qubit chip › Superconducting metal films › Niobium
      An elemental superconductor with a transition near 9.5 K, used for qubits and resonators.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: niobium, Annex II point (x).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: niobium; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 4.1 (Composition), second paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (x).
    - Tantalum CRM
      Material · Superconducting circuits › Qubit chip › Superconducting metal films › Tantalum
      A superconductor whose qubits on sapphire are among the best reported for quality.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: tantalum, Annex II point (ae).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: tantalum; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 4.1 (Composition), third paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ae).
  - Substrate
    Component · Superconducting circuits › Qubit chip › Substrate
    The single-crystal wafer that carries the circuit and holds most of its electric field energy.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: substrate*, wafer*; counted only when the title also names the platform.
    Sources
    - Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 3.2 (Substrate loss) and Sec. 2 (Dielectric loss).
    - Silicon CRM SRM
      Material · Superconducting circuits › Qubit chip › Substrate › Silicon
      High-quality crystalline silicon wafers, one of the two usual substrates.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: silicon metal, Annex II point (ac). Also a strategic raw material: silicon metal, Annex I point (o). The Annexes list silicon metal; wafers are not named.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: silicon; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 3.2 (Substrate loss).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ac); Annex I, Section 1, point (o).
    - Sapphire
      Material · Superconducting circuits › Qubit chip › Substrate › Sapphire
      Crystalline sapphire wafers, the other usual substrate.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Sapphire is a crystalline form of aluminium oxide; the Annexes list bauxite/alumina/aluminium. Not flagged until an expert confirms the mapping.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: sapphire; counted only when the title also names the platform.
      Sources
      Material matters in superconducting qubits, Murray, Conal E., Materials Science and Engineering: R: Reports 146, 100646 (Elsevier), 2021. Sec. 3.2 (Substrate loss) and Sec. 4.1 (tantalum qubits on sapphire).
  - Readout resonators and Purcell filters
    Component · Superconducting circuits › Qubit chip › Readout resonators and Purcell filters
    On-chip microwave resonators that read each qubit dispersively, with filters that stop the qubit decaying through the readout line.
    2 EU-funded projects · 2 organisations · 1 company (1 SME) · 2 countries · EU activity: low
    Companies in the most of these projects
    1. Silent Waves (FR): 1 project, SME
    Ownership (GLEIF): 1 of 1 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 1 companies checked.
    Title keywords: readout*, read-out*, purcell*, dispersive*; counted only when the title also names the platform.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. V A (Dispersive readout) and Sec. V D (Purcell filters).
- Cryogenic signal lines
  Subsystem · Superconducting circuits › Cryogenic signal lines
  Drive, flux and output lines that carry microwave and low-frequency signals between room temperature and the processor.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: cryogenic wiring, cryogenic cabling, cryogenic line*, signal line*, cabling.
  Sources
  - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 1.1 (Typical cabling) and Fig. 3.
  - Coaxial cables
    Component · Superconducting circuits › Cryogenic signal lines › Coaxial cables
    Semi-rigid microwave cables: stainless steel on drive lines, and superconducting niobium-titanium on the output lines between the coldest stages.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: coaxial*, coax.
    Sources
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 1.1, Sec. 2.1 (Fig. 1) and Sec. 3.4 (Output line configuration).
    - Niobium-titanium CRM SRM
      Material · Superconducting circuits › Cryogenic signal lines › Coaxial cables › Niobium-titanium
      A superconducting alloy used for low-loss cables and twisted pairs between the 4 K stage and the mixing chamber.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: niobium, Annex II point (x); titanium metal, Annex II point (af). Also a strategic raw material: titanium metal, Annex I point (p). An alloy of two listed raw materials, niobium and titanium metal.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: niobium-titanium, nbti.
      Sources
      Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.1 (NbTi twisted pairs) and Sec. 3.4 (NbTi coaxial cables).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (x); Annex II, Section 1, point (af); Annex I, Section 1, point (p).
  - Attenuators and filters
    Component · Superconducting circuits › Cryogenic signal lines › Attenuators and filters
    Cold attenuators and filters, anchored at each temperature stage, that suppress thermal noise travelling to the qubits.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: attenuator*, microwave filter*, low-pass filter*, bandpass filter*; counted only when the title also names the platform.
    Sources
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 1.1 and Sec. 2.2.1 (The need of attenuation).
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. III E 4 (Cryogenic engineering).
  - Circulators and isolators
    Component · Superconducting circuits › Cryogenic signal lines › Circulators and isolators
    Non-reciprocal parts that let the readout signal out while blocking noise travelling back to the chip.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: circulator*, isolator*, non-reciprocal*, nonreciprocal*.
    Sources
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 1.1 (Output lines) and Sec. 3.4 (Output line configuration).
- Readout amplifier chain
  Subsystem · Superconducting circuits › Readout amplifier chain
  Amplifiers that lift the very weak readout signal above the noise before it leaves the cryostat.
  2 EU-funded projects · 8 organisations · 2 companies (2 SMEs) · 6 countries · EU activity: low
  0 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Low Noise Factory AB (SE): 1 project, SME
  2. Silent Waves (FR): 1 project, SME
  Ownership (GLEIF): 2 of 2 companies checked; 0 of the 2 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 2 companies checked.
  Title keywords: amplifier*, amplification; counted only when the title also names the platform.
  Sources
  - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. V E (Parametric amplification).
  - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.4 (Output line configuration).
  - Josephson parametric amplifiers
    Component · Superconducting circuits › Readout amplifier chain › Josephson parametric amplifiers
    Near-quantum-limited first amplifiers at the coldest stage, including travelling-wave designs with gigahertz bandwidth.
    2 EU-funded projects · 8 organisations · 2 companies (2 SMEs) · 6 countries · EU activity: low
    Companies in the most of these projects
    1. Low Noise Factory AB (SE): 1 project, SME
    2. Silent Waves (FR): 1 project, SME
    Ownership (GLEIF): 2 of 2 companies checked; 0 of the 2 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 2 companies checked.
    Title keywords: josephson parametric*, travelling wave parametric*, traveling wave parametric*, twpa*, quantum-limited amplifier*.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. V E 2 and V E 3 (Josephson and travelling-wave parametric amplifiers).
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.4 (TWPA at the mixing chamber).
  - HEMT amplifiers
    Component · Superconducting circuits › Readout amplifier chain › HEMT amplifiers
    Low-noise high-electron-mobility transistor amplifiers at the 4 K stage, the second step of the chain.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: hemt*, high electron mobility transistor*, high-electron-mobility transistor*.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. V A (Fig. 20) and Sec. V E.
    - Engineering cryogenic setups for 100-qubit scale superconducting circuit systems, Krinner et al., EPJ Quantum Technology 6, 2 (Springer), 2019. Sec. 3.4 (HEMT amplifiers at the 4K stage).
- Room-temperature control electronics
  Subsystem · Superconducting circuits › Room-temperature control electronics
  Instruments that synthesise, shape and time the microwave pulses and digitise and process the returning readout signals.
  1 EU-funded project · 7 organisations · 1 company (1 SME) · 6 countries · EU activity: low
  Companies in the most of these projects
  1. Seeqc-Eu SRL (IT): 1 project, SME
  Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 1 companies checked.
  Title keywords: control electronics, control system*, control stack*, electronics; counted only when the title also names the platform.
  Sources
  - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. IV D 1 (Fig. 13), Sec. V B and Sec. VI (Summary and outlook).
  - Waveform generators and microwave sources
    Component · Superconducting circuits › Room-temperature control electronics › Waveform generators and microwave sources
    A microwave local oscillator mixed in IQ mixers with pulse envelopes from arbitrary waveform generators to drive the qubits.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: waveform generator*, awg*, microwave source*, signal generator*, iq mixer*.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. IV D 1 (Capacitive coupling for X,Y control), Fig. 13.
  - Readout mixers and digitisers
    Component · Superconducting circuits › Room-temperature control electronics › Readout mixers and digitisers
    Mixers that down-convert the readout signal, followed by sampling and digital signal processing that extract the qubit state.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: digitiser*, digitizer*, heterodyne*, demodulat*, signal processing; counted only when the title also names the platform.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. V B (I-Q mixing; homodyne and heterodyne demodulation), Fig. 22.
  - FPGA-based real-time control
    Component · Superconducting circuits › Room-temperature control electronics › FPGA-based real-time control
    Programmable logic, often custom-built, that provides fast classical feedback for measurement-based operations.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: fpga*, real-time control, feedback; counted only when the title also names the platform.
    Sources
    - A quantum engineer's guide to superconducting qubits, Krantz et al., Applied Physics Reviews 6, 021318 (AIP Publishing), 2019. Sec. VI (Summary and outlook).

Trapped ions (21 parts)

Trapped ions
Platform · Trapped ions
Qubits stored in the electronic states of single charged atoms held by electric fields in vacuum and controlled with lasers or microwaves.
13 EU-funded projects · 27 organisations · 8 companies (5 SMEs) · 11 countries · EU activity: medium
Companies in the most of these projects
1. Alpine Quantum Technologies GMBH (AT): 2 projects, SME
2. Bull SAS (FR): 2 projects
3. Toptica Photonics Se (DE): 2 projects
4. Akka Dsw GMBH (DE): 1 project
5. Creotech Instruments Spolka Akcyjna (PL): 1 project, SME
Ownership (GLEIF): 8 of 8 companies checked; 0 of the 3 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 100, from 8 companies checked.
Title keywords: trapped ion*, ion trap*, ion qubit*, trapped atomic ion*, ion chain*, ion crystal*, trapped-ion*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G06N10/40.
Sources
- Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. I A (Trapped ions for quantum computing) and Sec. II (Trapped ions as qubits).
- Ion trap
  Subsystem · Trapped ions › Ion trap
  An electrode structure whose radio-frequency and static fields hold a chain or array of ions in free space.
  5 EU-funded projects · 8 organisations · 1 company (1 SME) · 6 countries · EU activity: medium
  4 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Eleqtron GMBH (DE): 1 project, SME
  Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 40, from 1 companies checked.
  Title keywords: paul trap*, ion trap*, surface trap*, surface-electrode trap*, microfabricated trap*.
  Sources
  - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II A 1 to II A 3 (Types of ion traps; Paul traps; surface-electrode traps).
  - Surface-electrode trap chip
    Component · Trapped ions › Ion trap › Surface-electrode trap chip
    A trap with all electrodes in one plane on a chip, made with microfabrication and suited to many trapping zones.
    1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
    No company takes part in these projects.
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: surface trap*, surface-electrode*, microfabricated trap*, trap chip*, chip-scale trap*, trap array*.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II A 3 (Miniature, microfabricated and surface-electrode traps) and Sec. V A (Chip-scale ion traps).
  - RF drive and electrode voltages
    Component · Trapped ions › Ion trap › RF drive and electrode voltages
    A radio-frequency drive of 10 to 1000 V plus many static voltages, increasingly from digital-to-analog converters, that confine and move the ions.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: rf drive, dac*, digital-to-analog*, voltage source*, trap electronics; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II A 1 (RF amplitudes of 10-1000 V at 10-100 MHz) and Sec. V D (Integrated electronics).
  - Atom source and photoionisation
    Component · Trapped ions › Ion trap › Atom source and photoionisation
    A hot atomic vapour ionised by lasers that supplies ions of the chosen element.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: photoioni*, ion loading, atomic oven*, ablation; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II A 4 (Loading ions into traps).
    - Calcium
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Calcium
      Calcium-40 and calcium-43 ions are used in many of the reported gate demonstrations.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: calcium, 40ca, 43ca; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species).
    - Ytterbium
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Ytterbium
      Experiments with ytterbium-171 ions mostly use its hyperfine clock-state qubit.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Ytterbium is a rare earth element. Annex II lists heavy and light rare earth elements without naming which elements they cover, so it is not flagged.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: ytterbium, 171yb; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species).
    - Strontium CRM
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Strontium
      Strontium-88 ions are among the demonstrated qubit species.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: strontium, Annex II point (ad).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: strontium, 88sr; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ad).
    - Beryllium CRM
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Beryllium
      Beryllium-9 ions are used for laser-driven Raman gates.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: beryllium, Annex II point (e).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: beryllium, 9be; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (e).
    - Magnesium CRM
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Magnesium
      Magnesium ions serve as qubits and, in dual-species chains, for cooling other ions.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: magnesium, Annex II point (t). Annex I lists magnesium metal; the source does not say in which form magnesium is supplied, so the strategic flag is not set.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: magnesium, 25mg; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species) and Sec. IV B 3 (Dual-species ion systems).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (t).
    - Barium
      Material · Trapped ions › Ion trap › Atom source and photoionisation › Barium
      Barium-138 ions are used in dual-species chains, for example with ytterbium.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. The Annexes list baryte, a mineral, not barium; not flagged until an expert confirms.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: barium, 138ba, 133ba; counted only when the title also names the platform.
      Sources
      Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B (Table I, gate fidelities by species) and Sec. IV B 3 (Dual-species ion systems).
- Ultra-high-vacuum system
  Subsystem · Trapped ions › Ultra-high-vacuum system
  A vacuum chamber, sometimes cooled cryogenically, that makes collisions with background gas rare enough for ions to stay trapped for hours.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: ultra-high vacuum, uhv, vacuum system*, vacuum chamber*, vacuum; counted only when the title also names the platform.
  Sources
  - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II A 1 (Types of ion traps) and Sec. VI (Outlook).
  - Vacuum chamber with optical windows
    Component · Trapped ions › Ultra-high-vacuum system › Vacuum chamber with optical windows
    The sealed chamber whose windows let laser beams in and fluorescence out to lenses outside.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: vacuum chamber*, viewport*, vacuum window*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. V B (light through vacuum chamber windows) and Sec. III C (collection lenses outside the vacuum chamber).
  - Cryogenic trap environment
    Component · Trapped ions › Ultra-high-vacuum system › Cryogenic trap environment
    Cooling the trap below about 10 K lowers both the pressure and the unwanted heating of the ions’ motion.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: cryogenic*, cryostat*, cryo*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. II C 2 (Anomalous motional heating) and Sec. VI (Outlook).
- Laser and optical control
  Subsystem · Trapped ions › Laser and optical control
  Several lasers at different wavelengths, steered and switched by optical modulators, that cool, prepare, manipulate and read out the ions.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: laser*, optical control, optical addressing, light delivery; counted only when the title also names the platform.
  Sources
  - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. V B (Integrated photonics for light delivery) and Sec. III A (State preparation).
  - Lasers at the atomic transition wavelengths
    Component · Trapped ions › Laser and optical control › Lasers at the atomic transition wavelengths
    Typically around five lasers matched to the transitions of the species used, such as 397 nm and 729 nm light for calcium.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: laser*, laser system*, ultraviolet laser*, uv laser*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. V B (typically around five wavelengths) and Sec. III C (397 nm and 729 nm for calcium).
  - Acousto-optic modulators
    Component · Trapped ions › Laser and optical control › Acousto-optic modulators
    Devices that switch laser beams fast and fine-tune their frequency and phase.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: acousto-optic*, aom*, modulator*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III B 2 (Single-qubit gates) and Sec. V B (Integrated photonics for light delivery).
  - Integrated light delivery
    Component · Trapped ions › Laser and optical control › Integrated light delivery
    On-chip waveguides and grating couplers that route and focus light to each ion instead of free-space optics.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: integrated photonic*, integrated optic*, waveguide*, grating coupler*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. V B (Integrated photonics for light delivery).
- State detection
  Subsystem · Trapped ions › State detection
  Fluorescence from the ions is collected by optics and counted by single-photon detectors to read each qubit.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: detection, detector*, readout, read-out, fluorescence; counted only when the title also names the platform.
  Sources
  - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III C (State detection).
  - Collection optics
    Component · Trapped ions › State detection › Collection optics
    Lenses, mostly outside the vacuum chamber, whose numerical aperture sets the share of photons collected.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: collection optic*, objective*, lens*, imaging; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III C (State detection), photon collection efficiency.
  - Photomultipliers, cameras and avalanche photodiodes
    Component · Trapped ions › State detection › Photomultipliers, cameras and avalanche photodiodes
    The usual detectors of the blue to ultraviolet photons, with efficiencies of about 20 to 40 percent.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: photomultiplier*, pmt*, emccd*, camera*, avalanche photodiode*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III C (State detection), detector efficiencies.
  - Superconducting nanowire detectors
    Component · Trapped ions › State detection › Superconducting nanowire detectors
    Cryogenic detectors with higher efficiency for ultraviolet photons, also built into trap chips.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: snspd*, superconducting nanowire*, nanowire detector*, single-photon detector*; counted only when the title also names the platform.
    Sources
    - Trapped-ion quantum computing: Progress and challenges, Bruzewicz et al., Applied Physics Reviews 6, 021314 (AIP Publishing), 2019. Sec. III C (State detection) and Sec. V C (Integrated optics and detectors for light collection).

Neutral atoms (18 parts)

Neutral atoms
Platform · Neutral atoms
Qubits stored in single neutral atoms held in arrays of focused laser beams, with interactions through highly excited Rydberg states.
22 EU-funded projects · 63 organisations · 17 companies (12 SMEs) · 19 countries · EU activity: high
Companies in the most of these projects
1. Pasqal (FR): 3 projects, SME
2. Thales (FR): 2 projects
3. Eurice European Research and Project Office GMBH (DE): 1 project, SME
4. Hqs Quantum Simulations GMBH (DE): 1 project, SME
5. Infineon Technologies Austria AG (AT): 1 project
Ownership (GLEIF): 17 of 17 companies checked; 0 of the 6 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 209, from 17 companies checked.
Title keywords: neutral atom*, rydberg*, atom array*, atomic array*, tweezer array*, optical tweezer*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G06N10/40.
Sources
- Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2 (Neutral atoms arrays) and Fig. 2.
- Atomic register and vacuum system
  Subsystem · Neutral atoms › Atomic register and vacuum system
  A dilute atomic vapour in an ultra-high vacuum is laser-cooled in a magneto-optical trap before single atoms are loaded into the register.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: vacuum*, magneto-optical*, atomic vapour*, atomic vapor*, cold atom*, ultracold atom*; counted only when the title also names the platform.
  Sources
  - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Fig. 3.
  - Ultra-high-vacuum chamber
    Component · Neutral atoms › Atomic register and vacuum system › Ultra-high-vacuum chamber
    A room-temperature vacuum chamber that holds the atoms and, in the design described, the focusing lenses.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: vacuum*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Fig. 3(b).
    - Rubidium
      Material · Neutral atoms › Atomic register and vacuum system › Ultra-high-vacuum chamber › Rubidium
      A common atomic species whose two hyperfine ground states serve as the qubit.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: rubidium, 87rb; counted only when the title also names the platform.
      Sources
      Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2 (introduction) and Sec. 2.2.1 (Digital quantum processing).
  - Magneto-optical trap
    Component · Neutral atoms › Atomic register and vacuum system › Magneto-optical trap
    A laser cooling and trapping stage that prepares a cold cloud of about a million atoms.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: magneto-optical trap*, mot, laser cooling, laser-cooled; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading).
- Optical tweezer array
  Subsystem · Neutral atoms › Optical tweezer array
  A trapping laser shaped into many microscopic traps that each hold at most one atom, with moving tweezers that rearrange atoms into a defect-free pattern.
  1 EU-funded project · 2 organisations · 0 companies (0 SMEs) · 1 country · EU activity: low
  No company takes part in these projects.
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: tweezer*, optical trap*, trapping laser*; counted only when the title also names the platform.
  Sources
  - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading), Fig. 3 and Fig. 5.
  - Trapping laser
    Component · Neutral atoms › Optical tweezer array › Trapping laser
    A high-power laser whose output power, with the optics, limits how many tweezers and so qubits can be made.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: trapping laser*, high-power laser*, laser*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Sec. 2.2.3 (Prospects for improving the QPUs performances).
  - Spatial light modulator
    Component · Neutral atoms › Optical tweezer array › Spatial light modulator
    A device that imprints an adjustable phase pattern on the trapping beam to create the pattern of traps.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: spatial light modulator*, slm*, holograph*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Fig. 3(a).
  - Acousto-optic deflectors
    Component · Neutral atoms › Optical tweezer array › Acousto-optic deflectors
    Two-axis deflectors that steer the moving tweezers used to rearrange the atoms.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: acousto-optic*, deflector*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Fig. 3(a).
  - High-numerical-aperture lenses
    Component · Neutral atoms › Optical tweezer array › High-numerical-aperture lenses
    Lenses that focus the trapping light to spots about a micrometre across.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: high numerical aperture, objective*, lens*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading).
- Processing lasers
  Subsystem · Neutral atoms › Processing lasers
  Lasers that drive Raman transitions for single-qubit gates and excite Rydberg states for interactions, shaped by optical modulators.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: raman, rydberg laser*, rydberg excitation*, laser*; counted only when the title also names the platform.
  Sources
  - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Fig. 2 and Sec. 2.2.1 (Digital quantum processing).
  - Raman and Rydberg lasers
    Component · Neutral atoms › Processing lasers › Raman and Rydberg lasers
    Laser systems at the wavelengths needed for Raman gates and for Rydberg excitation.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: raman laser*, rydberg laser*, rydberg excitation*, raman transition*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Fig. 2 and Sec. 2.2.1 (Digital quantum processing).
  - Acousto- and electro-optic modulators
    Component · Neutral atoms › Processing lasers › Acousto- and electro-optic modulators
    Modulators on the laser beams, driven by direct digital synthesisers, that set pulse length, intensity, detuning and phase.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: electro-optic*, acousto-optic*, modulator*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.2.1 (Digital quantum processing).
- Fluorescence imaging
  Subsystem · Neutral atoms › Fluorescence imaging
  The atoms are imaged by collecting their fluorescence on a sensitive camera, both to rearrange the register and to read out results.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: imaging, camera*, fluorescence, readout, read-out, detection; counted only when the title also names the platform.
  Sources
  - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading) and Sec. 2.1.2 (Register readout).
  - EMCCD camera
    Component · Neutral atoms › Fluorescence imaging › EMCCD camera
    An electron-multiplying CCD camera that turns faint fluorescence into a measurable signal.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: emccd*, camera*, ccd*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.2 (Register readout).
  - Dichroic mirror
    Component · Neutral atoms › Fluorescence imaging › Dichroic mirror
    A mirror that separates the fluorescence of the atoms from the trapping light.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: dichroic*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Fig. 3(a) caption.
- Control electronics and computing
  Subsystem · Neutral atoms › Control electronics and computing
  FPGAs, GPUs, synthesisers and waveform generators that run the real-time rearrangement and the pulse sequences.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: fpga*, gpu*, control electronics, control system*; counted only when the title also names the platform.
  Sources
  - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Fig. 2 and Sec. 2.1.1 (Register loading).
  - FPGA and GPU rearrangement
    Component · Neutral atoms › Control electronics and computing › FPGA and GPU rearrangement
    Image analysis through an FPGA and a GPU that computes the moves sent to the deflector drivers.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: fpga*, gpu*, real-time; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Sec. 2.1.1 (Register loading).
  - Synthesisers and waveform generators
    Component · Neutral atoms › Control electronics and computing › Synthesisers and waveform generators
    Direct digital synthesisers and arbitrary waveform generators that drive the modulators and deflectors.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: direct digital synthes*, dds, waveform generator*, awg*; counted only when the title also names the platform.
    Sources
    - Quantum computing with neutral atoms, Henriet et al., Quantum 4, 327 (Verein zur Förderung des Open Access Publizierens in den Quantenwissenschaften), 2020. Fig. 2 and Sec. 2.2.1 (Digital quantum processing).

Photonic (19 parts)

Photonic
Platform · Photonic
Qubits carried by single photons, processed with linear optical circuits and measured with single-photon detectors.
61 EU-funded projects · 126 organisations · 36 companies (26 SMEs) · 22 countries · EU activity: high
46 of these projects name the part itself; the others come from its parts.
Companies in the most of these projects
1. Quandela (FR): 4 projects, SME
2. Ephos SRL (IT): 3 projects, SME
3. Single Quantum BV (NL): 3 projects, SME
4. IBM Research GMBH (CH): 2 projects
5. Qti SRL (IT): 2 projects
Ownership (GLEIF): 36 of 36 companies checked; 0 of the 8 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 149, from 36 companies checked.
Title keywords: photonic quantum*, photonic qubit*, quantum photonic*, linear optic*, boson sampling, single photon*, single-photon*, photon pair*, integrated photonic*, squeez*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G06N10/40.
Sources
- Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. I (Introduction) and Sec. II (Photon technology).
- Photon sources
  Subsystem · Photonic › Photon sources
  Sources of single photons or photon pairs that must be efficient, pure and identical.
  10 EU-funded projects · 14 organisations · 2 companies (2 SMEs) · 7 countries · EU activity: medium
  8 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Quandela (FR): 2 projects, SME
  2. Swabian Instruments GMBH (DE): 1 project, SME
  Ownership (GLEIF): 2 of 2 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 8, from 2 companies checked.
  Title keywords: photon source*, single-photon source*, photon pair*, photon-pair*, entangled photon*.
  Sources
  - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II B (Generating a photon) and Sec. II C (Generating a photon deterministically).
  - Parametric photon-pair sources
    Component · Photonic › Photon sources › Parametric photon-pair sources
    A pump laser in a nonlinear crystal or waveguide that now and then produces a heralded photon pair, by down-conversion or four-wave mixing.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: parametric down-conversion, down-conversion, spdc, periodically poled*, four-wave mixing.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II B (Generating a photon), Sec. II C and Sec. II E (four-wave mixing).
    - Potassium titanyl phosphate (KTP)
      Material · Photonic › Photon sources › Parametric photon-pair sources › Potassium titanyl phosphate (KTP)
      A nonlinear crystal suited to down-conversion of photon pairs at telecom wavelengths.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. The Annexes list titanium metal and phosphorus, not titanyl phosphate crystals; not flagged until an expert confirms.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: ktp, potassium titanyl phosphate.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II B (Generating a photon), group velocity matching.
  - Quantum-dot single-photon sources
    Component · Photonic › Photon sources › Quantum-dot single-photon sources
    Semiconductor quantum dots that emit single photons on demand, in free space or inside waveguides.
    3 EU-funded projects · 11 organisations · 2 companies (2 SMEs) · 6 countries · EU activity: low
    Companies in the most of these projects
    1. Quandela (FR): 1 project, SME
    2. Swabian Instruments GMBH (DE): 1 project, SME
    Ownership (GLEIF): 2 of 2 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 8, from 2 companies checked.
    Title keywords: quantum dot*, quantum-dot*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II C (Generating a photon deterministically).
  - Multiplexing switch networks
    Component · Photonic › Photon sources › Multiplexing switch networks
    Fast optical switches, set by logic such as an FPGA, that combine probabilistic sources into a nearly deterministic one.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: multiplex*, optical switch*, switch network*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II C (Generating a photon deterministically) and Fig. 1.
- Integrated photonic circuits
  Subsystem · Photonic › Integrated photonic circuits
  Waveguide chips that hold interferometers, phase shifters, switches and sources compactly enough to scale.
  25 EU-funded projects · 82 organisations · 24 companies (16 SMEs) · 18 countries · EU activity: high
  21 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Ephos SRL (IT): 2 projects, SME
  2. Qti SRL (IT): 2 projects
  3. Quix Quantum BV (NL): 2 projects, SME
  4. Celare Quantum Communications Aps (DK): 1 project, SME
  5. IBM Research GMBH (CH): 1 project
  Ownership (GLEIF): 24 of 24 companies checked; 0 of the 6 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 67, from 24 companies checked.
  Title keywords: integrated photonic*, photonic chip*, photonic integrated*, photonic circuit*, integrated optic*.
  Sources
  - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II D (Manipulating a photon) and Sec. II E (Integrated quantum photonics).
  - Waveguide material platforms
    Component · Photonic › Integrated photonic circuits › Waveguide material platforms
    The materials the chips are made of, among them laser-written glass, lithium niobate and silicon.
    4 EU-funded projects · 5 organisations · 1 company (1 SME) · 3 countries · EU activity: low
    0 of these projects name the part itself; the others come from its parts.
    Companies in the most of these projects
    1. Ephos SRL (IT): 1 project, SME
    Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 1 companies checked.
    Title keywords: waveguide*, photonic platform*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II E (Integrated quantum photonics).
    - Lithium niobate CRM
      Material · Photonic › Integrated photonic circuits › Waveguide material platforms › Lithium niobate
      An established integrated-optics crystal used for photon sources and fast electro-optic switches.
      2 EU-funded projects · 3 organisations · 0 companies (0 SMEs) · 3 countries · EU activity: low
      Critical raw material: lithium, Annex II point (s); niobium, Annex II point (x). A compound of two listed raw materials, lithium and niobium. Annex I lists only battery-grade lithium, so the strategic flag is not set.
      No company takes part in these projects.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: lithium niobate, linbo3.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II E (Integrated quantum photonics).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (s); Annex II, Section 1, point (x).
    - Silicon CRM SRM
      Material · Photonic › Integrated photonic circuits › Waveguide material platforms › Silicon
      Silicon chips offer dense, low-loss circuits compatible with existing foundry processes.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: silicon metal, Annex II point (ac). Also a strategic raw material: silicon metal, Annex I point (o). The Annexes list silicon metal; wafers are not named.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: silicon photonic*, silicon chip*, silicon; counted only when the title also names the platform.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II E (Integrated quantum photonics) and Fig. 2.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ac); Annex I, Section 1, point (o).
    - Glass for laser-written waveguides
      Material · Photonic › Integrated photonic circuits › Waveguide material platforms › Glass for laser-written waveguides
      Glass in which femtosecond lasers write three-dimensional waveguide networks.
      2 EU-funded projects · 2 organisations · 1 company (1 SME) · 1 country · EU activity: low
      Not marked as a critical raw material.
      Companies in the most of these projects
      Ephos SRL (IT): 1 project, SME
      Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 1 companies checked.
      Title keywords: laser-written*, laser written*, femtosecond-laser*, glass; counted only when the title also names the platform.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II E (Integrated quantum photonics).
  - Interferometers, phase shifters and couplers
    Component · Photonic › Integrated photonic circuits › Interferometers, phase shifters and couplers
    Beam splitters, thermo-optic phase shifters, waveguide crossings and grating couplers that make up reconfigurable circuits.
    1 EU-funded project · 2 organisations · 0 companies (0 SMEs) · 1 country · EU activity: low
    No company takes part in these projects.
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: interferomet*, phase shifter*, beam splitter*, beamsplitter*, grating coupler*, reconfigurable; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II E (Integrated quantum photonics) and Fig. 2 caption.
  - Electro-optic switches and modulators
    Component · Photonic › Integrated photonic circuits › Electro-optic switches and modulators
    Pockels cells and integrated electro-optic modulators that switch polarisation or path quickly.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: electro-optic*, pockels*, modulator*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II D (Manipulating a photon).
- Single-photon detectors
  Subsystem · Photonic › Single-photon detectors
  Detectors that register single photons; their efficiency sets how many photons a computation can use.
  1 EU-funded project · 2 organisations · 0 companies (0 SMEs) · 1 country · EU activity: low
  No company takes part in these projects.
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: single-photon detect*, single photon detect*, photon-number resolv*, photon number resolv*.
  Sources
  - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
  - Superconducting nanowire detectors
    Component · Photonic › Single-photon detectors › Superconducting nanowire detectors
    Nanowires biased near their critical current that register single photons with efficiencies above 90 percent at telecom wavelengths.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: snspd*, superconducting nanowire*, nanowire detector*, nanowire single-photon*.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
  - Transition-edge sensors
    Component · Photonic › Single-photon detectors › Transition-edge sensors
    Superconducting sensors that count how many photons arrive, at the cost of slow reset.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: transition-edge*, transition edge*, tes.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
  - Avalanche photodiodes
    Component · Photonic › Single-photon detectors › Avalanche photodiodes
    Silicon devices, which do not cover the telecom bands, and InGaAs devices for 1550 nm, simpler to run but less efficient.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: avalanche photodiode*, apd*, spad*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
    - Silicon CRM SRM
      Material · Photonic › Single-photon detectors › Avalanche photodiodes › Silicon
      The material of the Geiger-mode avalanche photodiodes long used in optical quantum experiments.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: silicon metal, Annex II point (ac). Also a strategic raw material: silicon metal, Annex I point (o). The Annexes list silicon metal; devices are not named.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: silicon; counted only when the title also names the platform.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ac); Annex I, Section 1, point (o).
    - Indium gallium arsenide (InGaAs) CRM SRM
      Material · Photonic › Single-photon detectors › Avalanche photodiodes › Indium gallium arsenide (InGaAs)
      The semiconductor of avalanche photodiodes for the 1550 nm telecom band.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: gallium, Annex II point (m); arsenic, Annex II point (b). Also a strategic raw material: gallium, Annex I point (f). A compound containing two listed raw materials, gallium and arsenic; indium is not listed.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: ingaas, indium gallium arsenide.
      Sources
      Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (m); Annex II, Section 1, point (b); Annex I, Section 1, point (f).
  - Detector cryostat
    Component · Photonic › Single-photon detectors › Detector cryostat
    Cooling to about 0.8 to 3 K that superconducting nanowire detectors need.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: cryostat*, cryogenic*, cryo*; counted only when the title also names the platform.
    Sources
    - Photonic quantum information processing: A concise review, Slussarenko et al., Applied Physics Reviews 6, 041303 (AIP Publishing), 2019. Sec. II A (Detecting a photon).

Spin qubits in semiconductors (21 parts)

Spin qubits in semiconductors
Platform · Spin qubits in semiconductors
Qubits stored in the spins of single electrons or holes in gate-defined quantum dots, or of donor atoms, in semiconductor chips.
68 EU-funded projects · 95 organisations · 25 companies (17 SMEs) · 21 countries · EU activity: high
Companies in the most of these projects
1. Abs Optronics GMBH (DE): 1 project
2. Amsys LTD (IL): 1 project, SME
3. Avantama AG (CH): 1 project, SME
4. Bioobst Gornitz GMBH Co. KG (DE): 1 project, SME
5. Day One Societa A Responsabilita Limitata (IT): 1 project, SME
Ownership (GLEIF): 25 of 25 companies checked; 0 of the 7 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 20, from 25 companies checked.
Title keywords: spin qubit*, quantum dot*, quantum-dot*, donor*, silicon qubit*, germanium qubit*, hole spin*, electron spin*, singlet-triplet, exchange-only.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G06N10/40.
Sources
- Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. I (Introduction) and Sec. II (Basics of spin qubits).
- Semiconductor host material
  Subsystem · Spin qubits in semiconductors › Semiconductor host material
  The crystal or heterostructure in which charges are confined, chosen and purified to limit decoherence.
  4 EU-funded projects · 6 organisations · 1 company (1 SME) · 5 countries · EU activity: low
  2 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Quantum Motion Technologies LTD (GB): 1 project, SME
  Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 1 companies checked.
  Title keywords: heterostructure*, silicon, germanium, gaas, wafer*, substrate*, semiconductor material*; counted only when the title also names the platform.
  Sources
  - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A (Quantum confinement) and Fig. 3.
  - Silicon structures (Si/SiGe and Si-MOS)
    Component · Spin qubits in semiconductors › Semiconductor host material › Silicon structures (Si/SiGe and Si-MOS)
    Electrons confined in a buried silicon quantum well under silicon-germanium, or at a silicon-oxide interface.
    3 EU-funded projects · 5 organisations · 1 company (1 SME) · 4 countries · EU activity: low
    2 of these projects name the part itself; the others come from its parts.
    Companies in the most of these projects
    1. Quantum Motion Technologies LTD (GB): 1 project, SME
    Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 1 companies checked.
    Title keywords: sige, silicon-germanium, mos, cmos, silicon; counted only when the title also names the platform.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A 2 and III A 3 (Bandstructure engineering; Electrostatic gating) and Fig. 3(c,d).
    - Isotopically enriched silicon-28 CRM SRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Silicon structures (Si/SiGe and Si-MOS) › Isotopically enriched silicon-28
      Silicon purified towards silicon-28, an isotope without nuclear spin, which gives long spin coherence.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: silicon metal, Annex II point (ac). Also a strategic raw material: silicon metal, Annex I point (o). The Annexes list silicon metal; isotopically enriched silicon is not named.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: 28si, silicon-28, isotopically enriched, isotopically purified, enriched silicon.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. I (Introduction) and Sec. II B (Donor spin qubits).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ac); Annex I, Section 1, point (o).
    - Germanium (in silicon-germanium) CRM SRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Silicon structures (Si/SiGe and Si-MOS) › Germanium (in silicon-germanium)
      Silicon-germanium layers form the barriers around the silicon quantum well.
      2 EU-funded projects · 3 organisations · 1 company (1 SME) · 3 countries · EU activity: low
      Critical raw material: germanium, Annex II point (n). Also a strategic raw material: germanium, Annex I point (g).
      Companies in the most of these projects
      Quantum Motion Technologies LTD (GB): 1 project, SME
      Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 1 companies checked.
      Title keywords: germanium, sige, silicon-germanium; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A 3 (Electrostatic gating) and Fig. 3(d).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (n); Annex I, Section 1, point (g).
  - Gallium arsenide heterostructures
    Component · Spin qubits in semiconductors › Semiconductor host material › Gallium arsenide heterostructures
    GaAs/AlGaAs structures used in the early spin-qubit experiments, whose nuclear spins are a source of decoherence.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: gaas, gallium arsenide, algaas; counted only when the title also names the platform.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A (Quantum confinement), Fig. 3(b), and Sec. II C (Singlet-triplet qubits).
    - Gallium CRM SRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Gallium arsenide heterostructures › Gallium
      One of the two elements of gallium arsenide.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: gallium, Annex II point (m). Also a strategic raw material: gallium, Annex I point (f).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: gallium, gaas, gallium arsenide; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A (Quantum confinement).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (m); Annex I, Section 1, point (f).
    - Arsenic CRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Gallium arsenide heterostructures › Arsenic
      The other element of gallium arsenide.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: arsenic, Annex II point (b).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: arsenic, gaas, gallium arsenide; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A (Quantum confinement).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (b).
  - Germanium hole devices
    Component · Spin qubits in semiconductors › Semiconductor host material › Germanium hole devices
    Holes confined in germanium structures, whose strong spin-orbit coupling allows control by electric fields alone.
    3 EU-funded projects · 4 organisations · 1 company (1 SME) · 4 countries · EU activity: low
    Companies in the most of these projects
    1. Quantum Motion Technologies LTD (GB): 1 project, SME
    Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 1 companies checked.
    Title keywords: germanium, hole spin*, hole qubit*; counted only when the title also names the platform.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. V A 4 and Sec. V E 3 (Holes in Si and Ge/GeSi), Fig. 8(k).
    - Germanium CRM SRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Germanium hole devices › Germanium
      The host material of hole spin qubits.
      1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
      Critical raw material: germanium, Annex II point (n). Also a strategic raw material: germanium, Annex I point (g).
      No company takes part in these projects.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: germanium; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. V E 3 (Holes in Si and Ge/GeSi).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (n); Annex I, Section 1, point (g).
  - Phosphorus donors in silicon
    Component · Spin qubits in semiconductors › Semiconductor host material › Phosphorus donors in silicon
    Single phosphorus atoms placed in silicon whose electron and nuclear spins serve as qubits.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: donor*, phosphorus, 31p.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. II B (Donor spin qubits and Kane’s proposal).
    - Phosphorus CRM
      Material · Spin qubits in semiconductors › Semiconductor host material › Phosphorus donors in silicon › Phosphorus
      The donor element whose nuclear spin Kane proposed as a qubit.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: phosphorus, Annex II point (z).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: phosphorus, 31p.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. II B (Donor spin qubits and Kane’s proposal).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (z).
- Gate electrodes
  Subsystem · Spin qubits in semiconductors › Gate electrodes
  Nanoscale metal gates, often overlapping in several layers, that define the dots and tune their charge and coupling.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: gate electrode*, gate stack*, gate-defined, gate defined, electrostatic gat*.
  Sources
  - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III A 3 (Electrostatic gating) and Sec. III C (Isolating and detecting single charges).
  - Overlapping gate layers
    Component · Spin qubits in semiconductors › Gate electrodes › Overlapping gate layers
    Stacked gate layers patterned on top of the device that give tight, independent control of each dot.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: overlapping gate*, gate layer*, multilayer gate*.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III C (Isolating and detecting single charges) and Fig. 8(j).
    - Aluminium CRM SRM
      Material · Spin qubits in semiconductors › Gate electrodes › Overlapping gate layers › Aluminium
      Aluminium is one metal used for overlapping gate stacks on silicon-germanium.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: bauxite/alumina/aluminium, Annex II point (c). Also a strategic raw material: bauxite/alumina/aluminium, Annex I point (a).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: aluminium, aluminum; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Fig. 8(j) caption, Sec. III C.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (c); Annex I, Section 1, point (a).
- Spin control
  Subsystem · Spin qubits in semiconductors › Spin control
  Oscillating magnetic or electric fields that rotate individual spins.
  1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
  No company takes part in these projects.
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: spin control, spin resonance, esr, edsr, spin manipulation, coherent control; counted only when the title also names the platform.
  Sources
  - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III D (Zeeman interactions and spin-orbit coupling) and Sec. V A (Loss-DiVincenzo single spin qubits).
  - Spin resonance striplines
    Component · Spin qubits in semiconductors › Spin control › Spin resonance striplines
    An on-chip line carrying an alternating current whose magnetic field drives spin rotations.
    1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
    No company takes part in these projects.
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: spin resonance, esr, stripline*, microwave antenna*; counted only when the title also names the platform.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. V A (Loss-DiVincenzo single spin qubits), single spin ESR.
  - Micromagnets
    Component · Spin qubits in semiconductors › Spin control › Micromagnets
    Small magnets that create a field gradient so that an electric drive can rotate the spin.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: micromagnet*, micro-magnet*, edsr, electric dipole spin*.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III D (Zeeman interactions and spin-orbit coupling) and Sec. V A 4 (cobalt micromagnet).
    - Cobalt CRM SRM
      Material · Spin qubits in semiconductors › Spin control › Micromagnets › Cobalt
      A cobalt micromagnet has been used to control spins in silicon-germanium double dots.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: cobalt, Annex II point (h). Also a strategic raw material: cobalt, Annex I point (d).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: cobalt; counted only when the title also names the platform.
      Sources
      Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. V A 4 (Limits of fidelity - randomized benchmarking), Co micromagnet.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (h); Annex I, Section 1, point (d).
- Charge sensing and readout
  Subsystem · Spin qubits in semiconductors › Charge sensing and readout
  Nearby sensors detect single charges, and so spin states after spin-to-charge conversion, using radio-frequency techniques for speed.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: charge sens*, charge detect*, readout, read-out, reflectometry, single-shot; counted only when the title also names the platform.
  Sources
  - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III C (Isolating and detecting single charges).
  - Point contacts and sensor dots
    Component · Spin qubits in semiconductors › Charge sensing and readout › Point contacts and sensor dots
    Quantum point contacts or extra quantum dots whose current changes with the charge of the qubit dots.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: quantum point contact*, qpc*, sensor dot*, charge sensor*, single-electron transistor*.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III C (Isolating and detecting single charges), Fig. 9.
  - Radio-frequency reflectometry and gate sensing
    Component · Spin qubits in semiconductors › Charge sensing and readout › Radio-frequency reflectometry and gate sensing
    Reading the charge state from the reflection of a radio-frequency or microwave signal, including directly off a gate.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: reflectometry, dispersive sensing, gate sensing, gate-based readout, gate-based sensing.
    Sources
    - Semiconductor spin qubits, Burkard et al., Reviews of Modern Physics 95, 025003 (American Physical Society), 2023. Sec. III C (Isolating and detecting single charges).

Quantum key distribution systems (15 parts)

Quantum key distribution systems
Platform · Quantum key distribution systems
Systems that share secret keys over optical links, with security based on quantum physics.
20 EU-funded projects · 89 organisations · 37 companies (13 SMEs) · 19 countries · EU activity: high
16 of these projects name the part itself; the others come from its parts.
Companies in the most of these projects
1. Id Quantique SA (CH): 3 projects, SME
2. Quside Technologies SL (ES): 3 projects, SME
3. Telefonica Innovacion Digital SL (ES): 2 projects
4. Toshiba Europe Limited (GB): 2 projects
5. Adtran Networks Se (DE): 1 project
Ownership (GLEIF): 37 of 37 companies checked; 1 of the 11 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 173, from 37 companies checked.
Title keywords: quantum key distribution, qkd, quantum cryptograph*, quantum-secure communication*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: H04L9/0852.
Sources
- Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Introduction and section Main protocols and implementations.
- Transmitter
  Subsystem · Quantum key distribution systems › Transmitter
  The sender, which prepares weak light pulses that carry key information in their polarisation, phase or quadratures.
  4 EU-funded projects · 10 organisations · 4 companies (2 SMEs) · 6 countries · EU activity: low
  0 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Quside Technologies SL (ES): 3 projects, SME
  2. Id Quantique SA (CH): 1 project, SME
  3. Robert Bosch GMBH (DE): 1 project
  4. Toshiba Europe Limited (GB): 1 project
  Ownership (GLEIF): 4 of 4 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 78, from 4 companies checked.
  Title keywords: transmitter*, light source*, photon source*; counted only when the title also names the platform.
  Sources
  - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Main protocols and implementations.
  - Gain-switched laser diodes
    Component · Quantum key distribution systems › Transmitter › Gain-switched laser diodes
    The usual light source, which gives phase-randomised pulses at clock rates up to a few gigahertz.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: laser diode*, gain-switched*, laser*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in practical security (last paragraphs).
  - Amplitude and phase modulators
    Component · Quantum key distribution systems › Transmitter › Amplitude and phase modulators
    Active elements that encode each pulse, now also integrated on silicon photonic chips.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: modulator*, phase modulat*, intensity modulat*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Cost and robustness.
  - Quantum random number generators
    Component · Quantum key distribution systems › Transmitter › Quantum random number generators
    High-speed devices that draw random bits from quantum processes, whose development practical QKD has driven.
    4 EU-funded projects · 10 organisations · 4 companies (2 SMEs) · 6 countries · EU activity: low
    Companies in the most of these projects
    1. Quside Technologies SL (ES): 3 projects, SME
    2. Id Quantique SA (CH): 1 project, SME
    3. Robert Bosch GMBH (DE): 1 project
    4. Toshiba Europe Limited (GB): 1 project
    Ownership (GLEIF): 4 of 4 companies checked; 0 of the 1 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 78, from 4 companies checked.
    Title keywords: random number*, qrng*, randomness.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Introduction (Why practical challenges in QKD?).
- Quantum channel
  Subsystem · Quantum key distribution systems › Quantum channel
  The optical link between sender and receiver, whose loss limits point-to-point distance.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: fibre*, fiber*, free-space, free space, satellite*, quantum channel*; counted only when the title also names the platform.
  Sources
  - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Main protocols and implementations (fundamental limitations).
  - Single-mode telecom fibre
    Component · Quantum key distribution systems › Quantum channel › Single-mode telecom fibre
    Standard fibre losing about 0.2 dB per kilometre at 1550 nm, which keeps direct links to a few hundred kilometres.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: fibre*, fiber*, telecom*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Main protocols and implementations (fundamental limitations).
  - Free-space and satellite links
    Component · Quantum key distribution systems › Quantum channel › Free-space and satellite links
    Links through the air or to satellites, pursued to extend the reach of QKD.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: free-space, free space, satellite*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Introduction (ground-to-satellite QKD).
- Receiver
  Subsystem · Quantum key distribution systems › Receiver
  The recipient, which decodes the pulses with single-photon detectors or, for continuous-variable protocols, homodyne detection.
  2 EU-funded projects · 2 organisations · 2 companies (2 SMEs) · 2 countries · EU activity: low
  0 of these projects name the part itself; the others come from its parts.
  Companies in the most of these projects
  1. Celare Quantum Communications Aps (DK): 1 project, SME
  2. Photon Bridge B.V. (NL): 1 project, SME
  Ownership (GLEIF): 2 of 2 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 2 companies checked.
  Title keywords: receiver*, detector*, detection; counted only when the title also names the platform.
  Sources
  - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Main protocols and implementations.
  - Single-photon detectors
    Component · Quantum key distribution systems › Receiver › Single-photon detectors
    InGaAs avalanche photodiodes and superconducting nanowire detectors, whose efficiency and dead time set the key rate.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: single-photon detect*, single photon detect*, snspd*, avalanche photodiode*, apd*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Introduction and section Major challenges in performance and cost: Key rate.
    - Indium gallium arsenide (InGaAs) CRM SRM
      Material · Quantum key distribution systems › Receiver › Single-photon detectors › Indium gallium arsenide (InGaAs)
      The semiconductor of the avalanche photodiodes used at telecom wavelengths.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: gallium, Annex II point (m); arsenic, Annex II point (b). Also a strategic raw material: gallium, Annex I point (f). A compound containing two listed raw materials, gallium and arsenic; indium is not listed.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: ingaas, indium gallium arsenide.
      Sources
      Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Introduction and section Major challenges in performance and cost: Key rate.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (m); Annex II, Section 1, point (b); Annex I, Section 1, point (f).
  - Homodyne and heterodyne detectors
    Component · Quantum key distribution systems › Receiver › Homodyne and heterodyne detectors
    Detectors for continuous-variable QKD, now also built with germanium photodiodes on silicon chips.
    1 EU-funded project · 1 organisation · 1 company (1 SME) · 1 country · EU activity: low
    Companies in the most of these projects
    1. Celare Quantum Communications Aps (DK): 1 project, SME
    Ownership (GLEIF): 1 of 1 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 1 companies checked.
    Title keywords: homodyne*, heterodyne*, continuous-variable*, continuous variable*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Cost and robustness.
    - Germanium CRM SRM
      Material · Quantum key distribution systems › Receiver › Homodyne and heterodyne detectors › Germanium
      The photodiode material of chip-based homodyne and heterodyne detectors.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: germanium, Annex II point (n). Also a strategic raw material: germanium, Annex I point (g).
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: germanium; counted only when the title also names the platform.
      Sources
      Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Cost and robustness.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (n); Annex I, Section 1, point (g).
  - Planar lightwave circuit interferometers
    Component · Quantum key distribution systems › Receiver › Planar lightwave circuit interferometers
    Silica-on-silicon chips that replace fibre-based asymmetric Mach-Zehnder interferometers in phase-based receivers.
    2 EU-funded projects · 2 organisations · 2 companies (2 SMEs) · 2 countries · EU activity: low
    Companies in the most of these projects
    1. Celare Quantum Communications Aps (DK): 1 project, SME
    2. Photon Bridge B.V. (NL): 1 project, SME
    Ownership (GLEIF): 2 of 2 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 0, from 2 companies checked.
    Title keywords: planar lightwave*, interferomet*, photonic integrated*, integrated photonic*, chip-scale*; counted only when the title also names the platform.
    Sources
    - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Cost and robustness.
    - Silicon CRM SRM
      Material · Quantum key distribution systems › Receiver › Planar lightwave circuit interferometers › Silicon
      The wafer material of silica-on-silicon planar lightwave circuits.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: silicon metal, Annex II point (ac). Also a strategic raw material: silicon metal, Annex I point (o). The Annexes list silicon metal; wafers are not named.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: silicon; counted only when the title also names the platform.
      Sources
      Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Cost and robustness.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (ac); Annex I, Section 1, point (o).
- Classical post-processing
  Subsystem · Quantum key distribution systems › Classical post-processing
  Parameter estimation and error correction on large blocks of raw key data, needed for composable security.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: post-processing, error correction, privacy amplification, key distillation, reconciliation; counted only when the title also names the platform.
  CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: H04L9/0858.
  Sources
  - Practical challenges in quantum key distribution, Diamanti et al., npj Quantum Information 2, 16025 (Springer Nature), 2016. Section Major challenges in performance and cost: Distance (post-processing over large data blocks).

Quantum sensors and atomic clocks (17 parts)

Quantum sensors and atomic clocks
Platform · Quantum sensors and atomic clocks
Sensors and clocks that read atoms, spins or superconducting loops for magnetic fields, gravity, acceleration, rotation and time, including vapour-cell, cold-atom, diamond and SQUID devices used for navigation and timing without satellites.
47 EU-funded projects · 102 organisations · 28 companies (11 SMEs) · 22 countries · EU activity: high
Companies in the most of these projects
1. Nvision Quantum Technologies GMBH (DE): 3 projects, SME
2. Thales (FR): 3 projects
3. Airbus Defence and Space GMBH (DE): 2 projects
4. Airbus Defence and Space SAS (FR): 2 projects
5. Exail (FR): 2 projects
Ownership (GLEIF): 28 of 28 companies checked; 0 of the 10 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 153, from 28 companies checked.
Title keywords: quantum sensor*, quantum sensing, quantum metrolog*, atomic clock*, atom interferomet*, cold atom*, atomic magnetometer*, optically pumped magnetometer*, quantum magnetomet*, quantum gravimet*, nitrogen-vacancy.
Sources
- Quantum technology for military applications, Krelina, M., EPJ Quantum Technology 8, 24 (SpringerOpen), 2021. Sec. 3.4 (Quantum sensing and metrology, 3.4.1 and 3.4.2) and Sec. 4.2, Table 1 (TRL: inertial navigation 4-5, clocks 4-6, magnetic and gravity sensing 5-6).
- High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. I (Introduction) and Sec. III (System engineering).
- Alkali vapour cell sensors
  Subsystem · Quantum sensors and atomic clocks › Alkali vapour cell sensors
  Clocks and magnetometers that probe a warm vapour of rubidium or caesium atoms in a sealed cell with laser light.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: vapour cell*, vapor cell*, atomic vapour*, atomic vapor*, alkali vapour*, alkali vapor*; counted only when the title also names the platform.
  Sources
  - Chip-scale atomic devices, Kitching, J., Applied Physics Reviews 5, 031302 (AIP Publishing), 2018. Sec. I.B (Alkali vapor cells) and Sec. II (Micromachined alkali vapor cells).
  - Alkali vapour cells
    Component · Quantum sensors and atomic clocks › Alkali vapour cell sensors › Alkali vapour cells
    A sealed glass or silicon and glass cell holding rubidium or caesium vapour, usually with a buffer gas, that serves as the sensing medium of vapour-cell clocks and magnetometers.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: vapour cell*, vapor cell*, alkali cell*, mems cell*, microfabricated cell*; counted only when the title also names the platform.
    Sources
    - Chip-scale atomic devices, Kitching, J., Applied Physics Reviews 5, 031302 (AIP Publishing), 2018. Sec. II.B (Cell fabrication, Fig. 10) and II.C (Introduction of alkali atoms); maturity: glass-blown cells are used in most atomic clocks and magnetometers (Fig. 10 caption).
  - Chip-scale atomic clock physics packages
    Component · Quantum sensors and atomic clocks › Alkali vapour cell sensors › Chip-scale atomic clock physics packages
    A millimetre-scale stack of a vertical-cavity laser, micro-optics, a heated microfabricated cell and a photodetector that locks a local oscillator to an atomic resonance with tens of milliwatts.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: chip-scale atomic clock*, miniature atomic clock*, csac, physics package*; counted only when the title also names the platform.
    Sources
    - Chip-scale atomic devices, Kitching, J., Applied Physics Reviews 5, 031302 (AIP Publishing), 2018. Sec. III.C (Physics packages, Figs. 23-26), III.F (CSAC prototypes) and III.G (Performance and impact: commercial device released in 2011).
    - Quantum technology for military applications, Krelina, M., EPJ Quantum Technology 8, 24 (SpringerOpen), 2021. Sec. 3.4.2 (Clocks: chip-size clocks) and Table 1 (quantum clocks TRL 4-6).
  - Optically pumped magnetometer sensor heads
    Component · Quantum sensors and atomic clocks › Alkali vapour cell sensors › Optically pumped magnetometer sensor heads
    A compact head in which a laser pumps a heated alkali or helium cell and a photodiode reads the light, reaching femtotesla sensitivity near zero field in the spin-exchange-relaxation-free regime.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: optically pumped magnetometer*, atomic magnetometer*, serf magnetometer*, opm meg; counted only when the title also names the platform.
    Sources
    - Optically pumped magnetometers: From quantum origins to multi-channel magnetoencephalography, Tierney et al., NeuroImage 199, 598-608 (Elsevier), 2019. Sec. 2.2 (In a nutshell, Fig. 1) and Sec. 3.5 (Zero field and suppression of relaxation due to spin exchange); maturity: Sec. 5 (sensors sold, MEG systems not yet ready to use).
    - Quantum technology for military applications, Krelina, M., EPJ Quantum Technology 8, 24 (SpringerOpen), 2021. Sec. 3.4.1 and Table 1 (magnetic and gravity sensing TRL 5-6).
- Cold-atom inertial and gravity sensors
  Subsystem · Quantum sensors and atomic clocks › Cold-atom inertial and gravity sensors
  Sensors that laser-cool atoms in vacuum and use matter-wave interference to measure gravity, its gradients, acceleration or rotation.
  9 EU-funded projects · 23 organisations · 8 companies (2 SMEs) · 8 countries · EU activity: medium
  Companies in the most of these projects
  1. Airbus Defence and Space GMBH (DE): 2 projects
  2. Airbus Defence and Space SAS (FR): 2 projects
  3. Exail (FR): 2 projects
  4. Gac (FR): 2 projects, SME
  5. Gmv Aerospace and Defence SA (ES): 2 projects
  Ownership (GLEIF): 8 of 8 companies checked; 0 of the 5 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 7, from 8 companies checked.
  Title keywords: cold atom*, atom interferomet*, matter wave*, quantum gravimet*, quantum inertial; counted only when the title also names the platform.
  Sources
  - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. III (System engineering, Fig. 2), Sec. IV (Gravity sensors) and Sec. V (Inertial sensors).
  - Atom-interferometer sensor heads
    Component · Quantum sensors and atomic clocks › Cold-atom inertial and gravity sensors › Atom-interferometer sensor heads
    The sensor head that cools atoms in an ultra-high-vacuum chamber and splits and recombines them with Raman light pulses, so the interference phase gives gravity, a gradient, an acceleration or a rotation.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: atom interferomet*, quantum gravimet*, gravity gradiomet*, atom gyroscope*, atomic gyroscope*, quantum accelerometer*; counted only when the title also names the platform.
    Sources
    - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. IV.E (Commercial instruments) and IV.F (Applications: ship and aircraft operation), Sec. V.A (Gyroscopes) and V.B (Accelerometers).
    - Quantum technology for military applications, Krelina, M., EPJ Quantum Technology 8, 24 (SpringerOpen), 2021. Sec. 5.4 (Quantum PNT) and Table 1 (quantum inertial navigation TRL 4-5).
  - Magneto-optical trap optics
    Component · Quantum sensors and atomic clocks › Cold-atom inertial and gravity sensors › Magneto-optical trap optics
    Optics that deliver and shape the cooling beams of a magneto-optical trap, from fibre collimators in six-beam set-ups to single-beam pyramid and diffraction-grating chips.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: magneto-optical trap*, grating mot*, pyramid mot*, laser cooling, atom chip*; counted only when the title also names the platform.
    Sources
    - Contributed Review: The feasibility of a fully miniaturized magneto-optical trap for portable ultracold quantum technology, Rushton et al., Review of Scientific Instruments 85, 121501 (AIP Publishing), 2014. Sec. II (The magneto optical trap system: six-beam, mirror, pyramid, tetrahedral and grating MOTs, Figs. 1-2).
    - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. III.C (Optical subsystems: about ten collimators per sensor).
  - Cold-atom vacuum packages
    Component · Quantum sensors and atomic clocks › Cold-atom inertial and gravity sensors › Cold-atom vacuum packages
    A compact ultra-high-vacuum enclosure of bonded glass or silicon kept near one ten-billionth of a millibar by getters or small ion pumps, with alkali dispensers supplying the atoms.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: ultra-high vacuum, uhv, getter*, alkali dispenser*, vacuum cell*; counted only when the title also names the platform.
    Sources
    - Contributed Review: The feasibility of a fully miniaturized magneto-optical trap for portable ultracold quantum technology, Rushton et al., Review of Scientific Instruments 85, 121501 (AIP Publishing), 2014. Sec. III (Atom source and control: alkali metal dispensers) and Sec. IV (UHV in a chip: pumping, permeation, outgassing); maturity: Sec. VI (sealed cells feasible on paper, outgassing data needed).
    - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. III.A (Vacuum system: getter and ion pumps, non-magnetic chambers).
- Lasers for atomic sensors
  Subsystem · Quantum sensors and atomic clocks › Lasers for atomic sensors
  Frequency-stabilised laser systems that cool, prepare and read the atoms of field-deployable clocks and sensors.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: laser system*, frequency stabili*, narrow linewidth, frequency doubl*; counted only when the title also names the platform.
  Sources
  - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. III.B (Laser system, Figs. 3 and 4) and Fig. 2 (laser requirements).
  - Narrow-linewidth and frequency-doubled lasers
    Component · Quantum sensors and atomic clocks › Lasers for atomic sensors › Narrow-linewidth and frequency-doubled lasers
    Diode lasers at the alkali lines near 780 or 852 nanometres, or telecom lasers at 1560 nanometres frequency-doubled to 780, amplified and phase-locked for sensors that must work outside the laboratory.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: narrow linewidth laser*, frequency doubl*, telecom laser*, diode laser*, distributed feedback laser*; counted only when the title also names the platform.
    Sources
    - High-accuracy inertial measurements with cold-atom sensors, Geiger et al., AVS Quantum Science 2, 024702 (AIP Publishing), 2020. Sec. III.B (Laser system: telecom-doubled architecture with fibre amplifier and PPLN waveguide, Fig. 4b; fibred bench at TRL 4; qualified telecom parts for field and space use).
- Magnetic shielding and field control
  Subsystem · Quantum sensors and atomic clocks › Magnetic shielding and field control
  Passive shields and active coils that lower the residual magnetic field to the nanotesla level that atomic magnetometers and atom sensors need.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: magnetic shield*, magnetically shielded, mu-metal, field compensation, active shielding; counted only when the title also names the platform.
  Sources
  - Interference suppression techniques for OPM-based MEG: Opportunities and challenges, Seymour et al., NeuroImage 247, 118834 (Elsevier), 2022. Sec. 1.1 (shielded rooms of copper or aluminium and mu-metal) and Sec. 2 (Hardware for OPM interference suppression).
  - Mu-metal shields and shielded rooms
    Component · Quantum sensors and atomic clocks › Magnetic shielding and field control › Mu-metal shields and shielded rooms
    Layers of high-permeability mu-metal and conductive metal, from small sensor shields to magnetically shielded rooms, with degaussing to remove remanent fields.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: magnetic shield*, magnetically shielded room*, mu-metal, mumetal, degauss*; counted only when the title also names the platform.
    Sources
    - Interference suppression techniques for OPM-based MEG: Opportunities and challenges, Seymour et al., NeuroImage 247, 118834 (Elsevier), 2022. Sec. 1.1 (two to three layers usually sufficient) and Sec. 2 (four-layer mu-metal room, degaussing; a commercial OPM-optimised room).
  - Active field compensation coils
    Component · Quantum sensors and atomic clocks › Magnetic shielding and field control › Active field compensation coils
    Coils on the sensors and around the measurement volume, driven by reference sensors, that null the remaining static and slowly varying field.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: active shielding, field compensation, nulling coil*, compensation coil*, biplanar coil*; counted only when the title also names the platform.
    Sources
    - Interference suppression techniques for OPM-based MEG: Opportunities and challenges, Seymour et al., NeuroImage 247, 118834 (Elsevier), 2022. Sec. 2 (on-sensor nulling coils, external biplanar and matrix coils; static field reduced to about 0.29 nT).
- Diamond and superconducting magnetometers
  Subsystem · Quantum sensors and atomic clocks › Diamond and superconducting magnetometers
  Magnetometers built on solid-state spins in diamond or on superconducting quantum interference devices.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: nitrogen-vacancy, nv centre*, nv center*, diamond magnetomet*, squid*, superconducting quantum interference; counted only when the title also names the platform.
  Sources
  - Sensitivity optimization for NV-diamond magnetometry, Barry et al., Reviews of Modern Physics 92, 015004 (American Physical Society), 2020. Sec. I (Introduction) and Sec. VI (Diamond material engineering).
  - SQUIDs in biomagnetism: a roadmap towards improved healthcare, Körber et al., Superconductor Science and Technology 29, 113001 (IOP Publishing), 2016. Introduction (dc SQUID principle) and Ch. 1 (SQUIDs and measurement systems).
  - NV-diamond magnetometer elements
    Component · Quantum sensors and atomic clocks › Diamond and superconducting magnetometers › NV-diamond magnetometer elements
    Diamond plates or chips carrying ensembles of nitrogen-vacancy centres whose spin is read optically to sense magnetic fields at room temperature.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: nitrogen-vacancy, nv centre*, nv center*, diamond magnetomet*, nv diamond; counted only when the title also names the platform.
    Sources
    - Sensitivity optimization for NV-diamond magnetometry, Barry et al., Reviews of Modern Physics 92, 015004 (American Physical Society), 2020. Sec. VI.A to VI.E (conversion efficiency, synthesis, irradiation, annealing) and Table 3.
    - Quantum technology for military applications, Krelina, M., EPJ Quantum Technology 8, 24 (SpringerOpen), 2021. Sec. 3.4.1 (NV sensors: room temperature, centre fabrication a challenge).
    - Synthetic diamond with nitrogen-vacancy centres
      Material · Quantum sensors and atomic clocks › Diamond and superconducting magnetometers › NV-diamond magnetometer elements › Synthetic diamond with nitrogen-vacancy centres
      Single-crystal diamond grown by plasma chemical vapour deposition or high pressure and temperature, doped with nitrogen, irradiated and annealed, often enriched in carbon-12 to lengthen spin coherence.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Diamond is not an entry of either Annex of Regulation (EU) 2024/1252 (the Annexes name graphite, another form of carbon), so it is not flagged.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: cvd diamond, synthetic diamond*, single-crystal diamond, isotopically enriched diamond, diamond growth; counted only when the title also names the platform.
      Sources
      Sensitivity optimization for NV-diamond magnetometry, Barry et al., Reviews of Modern Physics 92, 015004 (American Physical Society), 2020. Sec. VI.C (Diamond synthesis and HPHT treatment, PE-CVD), VI.D (Electron irradiation), VI.E (Annealing) and Table 3 (13C at or below about 20 ppm); Sec. III (12C enrichment).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex I, Section 1 and Annex II, Section 1 (no entry for diamond).
  - SQUID magnetometer elements
    Component · Quantum sensors and atomic clocks › Diamond and superconducting magnetometers › SQUID magnetometer elements
    Superconducting loops with Josephson junctions, made from niobium films at 4 kelvin or high-temperature superconductors at 77 kelvin, that turn magnetic flux into a voltage for femtotesla magnetometers and gradiometers.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: squid*, superconducting quantum interference, high-tc squid*, squid magnetomet*; counted only when the title also names the platform.
    Sources
    - SQUIDs in biomagnetism: a roadmap towards improved healthcare, Körber et al., Superconductor Science and Technology 29, 113001 (IOP Publishing), 2016. Ch. 1 (low-Tc niobium SQUID systems), Ch. 3 (High transition temperature SQUIDs for MEG) and Ch. 8 (commercial roadmap: about 250 MEG systems with over 50,000 SQUIDs by end-2015).

Quantum memories for networks (18 parts)

Quantum memories for networks
Platform · Quantum memories for networks
Devices that map a photonic quantum state onto matter, hold it and release it on demand, needed by quantum repeaters.
13 EU-funded projects · 19 organisations · 6 companies (6 SMEs) · 8 countries · EU activity: medium
Companies in the most of these projects
1. Welinq SAS (FR): 2 projects, SME
2. AQLS UG (haftungsbeschränkt) (DE): 1 project, SME
3. Aurea Technology (FR): 1 project, SME
4. Qubig GMBH (DE): 1 project, SME
5. Qutools GMBH (DE): 1 project, SME
Ownership (GLEIF): 6 of 6 companies checked; 0 of the 0 EU-based companies with an LEI report a parent outside the EU. Quantum patent families (EPO) of these companies: 1, from 6 companies checked.
Title keywords: quantum memor*, photon storage, atomic memor*, light-matter interface*, optical quantum memor*.
CPC groups (scheme 2026.08), kept for patent counts per part, which are not queried yet: G11C13/04.
Sources
- Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Abstract and Sec. 1 (Introduction), second and third paragraphs.
- Storage media
  Subsystem · Quantum memories for networks › Storage media
  The material in which the quantum state is held: rare-earth-doped solids, colour centres in diamond or alkali atoms.
  1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
  0 of these projects name the part itself; the others come from its parts.
  No company takes part in these projects.
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: storage medium, memory medium, memory substrate*; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2 (Physical systems and their recent developments).
  - Rare-earth-doped crystals
    Component · Quantum memories for networks › Storage media › Rare-earth-doped crystals
    Crystals such as yttrium orthosilicate doped with praseodymium, europium, erbium or neodymium ions, valued for long coherence at cryogenic temperatures.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: rare-earth doped, rare earth doped, rare-earth-ion, doped crystal*, y2sio5, yso crystal*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.1 (Rare-earth-ion doped solids) and 2.2.1.1 (Spin storage and long coherence time in solids).
    - Yttrium (host lattice)
      Material · Quantum memories for networks › Storage media › Rare-earth-doped crystals › Yttrium (host lattice)
      Yttrium is the host of the yttrium orthosilicate crystals used by most praseodymium, europium and erbium memories.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Yttrium is a heavy rare earth element in the Commission's 2023 grouping, but Annex II lists heavy and light rare earth elements without naming the elements, so it is not flagged here; data/critical-materials.json records its listing, USGS facts and Chinese export control.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: yttrium, yttrium orthosilicate, y2sio5; counted only when the title also names the platform.
      Sources
      Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.1.1 (Pr3+:Y2SiO5 and Eu3+:Y2SiO5 storage experiments).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, points (q) and (r) (rare earth groups, elements not named).
    - Erbium, europium, praseodymium and thulium dopants
      Material · Quantum memories for networks › Storage media › Rare-earth-doped crystals › Erbium, europium, praseodymium and thulium dopants
      Rare-earth ions doped into the host crystal hold the stored state, erbium for the telecom band and europium for the longest storage.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. These are rare earth elements; Annex II lists the heavy and light groups without naming elements and Annex I names praseodymium only among rare earths for permanent magnets, so the node is not flagged; see data/critical-materials.json.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: erbium, europium, praseodymium, thulium; counted only when the title also names the platform.
      Sources
      Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.1 and 2.3.2.1 (Direct storage of telecom wavelengths in Er3+); Sec. 2.3.1.2 (Ti:Tm:LiNbO3 waveguide).
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, points (q) and (r); Annex I, Section 1, point (n).
  - Diamond colour centres
    Component · Quantum memories for networks › Storage media › Diamond colour centres
    Nitrogen-vacancy and related colour centres in diamond, whose electronic and nuclear spins can store states with optical access.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: nitrogen-vacancy, colour centre*, color center*, silicon-vacancy, nv centre*, nv center*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.2 (Nitrogen-vacancy centers in diamond).
    - Synthetic diamond
      Material · Quantum memories for networks › Storage media › Diamond colour centres › Synthetic diamond
      High-purity synthetic single-crystal diamond hosts the colour centres used as memories.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Diamond is not an entry of either Annex of Regulation (EU) 2024/1252, so it is not flagged.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: synthetic diamond*, cvd diamond, single-crystal diamond; counted only when the title also names the platform.
      Sources
      Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.2 (Nitrogen-vacancy centers in diamond), first paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex I, Section 1 and Annex II, Section 1 (no entry for diamond).
  - Alkali vapour cells and cold-atom sources
    Component · Quantum memories for networks › Storage media › Alkali vapour cells and cold-atom sources
    Warm vapour cells or laser-cooled clouds of rubidium or caesium atoms, whose large optical depth allows efficient storage.
    1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
    No company takes part in these projects.
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: vapour cell*, vapor cell*, cold atom*, atomic ensemble*, magneto-optical trap*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.4 (Alkali vapours).
    - Rubidium and caesium
      Material · Quantum memories for networks › Storage media › Alkali vapour cells and cold-atom sources › Rubidium and caesium
      The alkali metals whose atoms form the storage ensemble in vapour and cold-atom memories.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Not marked as a critical raw material. Neither rubidium nor caesium is an entry of either Annex of Regulation (EU) 2024/1252, so they are not flagged.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: rubidium, caesium, cesium; counted only when the title also names the platform.
      Sources
      Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.4 (Alkali vapours), experiments in rubidium and caesium.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex I, Section 1 and Annex II, Section 1 (no entry for rubidium or caesium).
- Control lasers and frequency references
  Subsystem · Quantum memories for networks › Control lasers and frequency references
  Narrow-linewidth lasers that prepare the medium and drive the write and read pulses of the memory.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: narrow-linewidth laser*, control laser*, frequency reference*, stabilised laser*, stabilized laser*; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.1 (Single photon storage) and 2.3.1.1 (Noise, control and read-write fields).
  - Narrow-linewidth lasers
    Component · Quantum memories for networks › Control lasers and frequency references › Narrow-linewidth lasers
    Frequency-stabilised continuous-wave and pulsed lasers matched to the transitions of the storage medium.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: narrow-linewidth laser*, laser stabili*, external-cavity diode laser*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.1, first paragraph (storage of bright laser pulses) and Sec. 2.3.2, first paragraph (availability of suitable lasers).
- Cryogenics
  Subsystem · Quantum memories for networks › Cryogenics
  Cryostats that cool rare-earth and solid-state memories to a few kelvin or below, where their coherence is long.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: cryostat*, cryogenic*, cryocooler*, dilution refrigerat*; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.1.1, first paragraph (coherence at cryogenic temperatures) and Sec. 2.3.2.1 (crystal cooled to 2.6 K).
  - Closed-cycle cryostats and dilution refrigerators
    Component · Quantum memories for networks › Cryogenics › Closed-cycle cryostats and dilution refrigerators
    Closed-cycle coolers reach a few kelvin for rare-earth crystals; dilution refrigerators reach millikelvin for electron-spin and microwave storage.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: closed-cycle cryostat*, pulse tube*, dilution refrigerat*, mixing chamber*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.2.1.1 (electron spin coherence of Er ions in YSO below 1 K; storage at 2 K).
    - Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Introduction, first paragraph.
    - Helium-3 and helium-4 CRM
      Material · Quantum memories for networks › Cryogenics › Closed-cycle cryostats and dilution refrigerators › Helium-3 and helium-4
      Helium is the coolant of the cryostats, and the helium-3 isotope is the working fluid of dilution refrigerators.
      0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
      Critical raw material: helium, Annex II point (p). Annex II lists helium without distinguishing its isotopes.
      Quantum patent families (EPO): not checked yet for these companies.
      Title keywords: helium-3, 3he, helium isotope*, liquid helium; counted only when the title also names the platform.
      Sources
      Neutron imaging of an operational dilution refrigerator, Lawson et al., Scientific Reports 12, 1130 (Springer Nature), 2022. Introduction, first paragraph.
      Regulation (EU) 2024/1252 of the European Parliament and of the Council of 11 April 2024 establishing a framework for ensuring a secure and sustainable supply of critical raw materials, European Parliament and Council of the European Union, Official Journal of the European Union, L series, 3 May 2024 (EUR-Lex), 2024. Annex II, Section 1, point (p).
- Single-photon detection and frequency conversion
  Subsystem · Quantum memories for networks › Single-photon detection and frequency conversion
  Detectors that read the retrieved photons and nonlinear converters that move them to or from telecom wavelengths.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: single-photon detector*, frequency conversion, frequency converter*, wavelength conversion; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.2 (Telecom wavelength storage), first paragraph, and 2.3.2.2 (Indirect storage of telecom wavelengths).
  - Single-photon detectors
    Component · Quantum memories for networks › Single-photon detection and frequency conversion › Single-photon detectors
    Detectors that register single retrieved photons, whose efficiency at the memory wavelength limits the link.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: single-photon detector*, superconducting nanowire*, snspd*, photon counter*; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.2, first paragraph (efficiency of detectors).
  - Frequency converters
    Component · Quantum memories for networks › Single-photon detection and frequency conversion › Frequency converters
    Periodically poled nonlinear waveguides and atomic converters that shift photons between memory and telecom wavelengths.
    0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
    Quantum patent families (EPO): not checked yet for these companies.
    Title keywords: frequency conversion, difference frequency generation, sum frequency generation, periodically poled, ppln; counted only when the title also names the platform.
    Sources
    - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.2.2 (Indirect storage of telecom wavelengths), second paragraph (PPLN waveguide conversion).
- Packaged memory modules
  Subsystem · Quantum memories for networks › Packaged memory modules
  Memories integrated in waveguides or fibres and packaged as units that a network builder can install.
  0 EU-funded projects · 0 organisations · 0 companies (0 SMEs) · 0 countries · EU activity: none
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: memory module*, integrated quantum memor*, waveguide memor*, fibre-integrated memor*, fiber-integrated memor*; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 2.3.3 (Integrability of implementations, nano and micro fabricated systems).
- Repeater nodes and network testbeds
  Subsystem · Quantum memories for networks › Repeater nodes and network testbeds
  Repeater stations and testbeds that use memories to synchronise entanglement swapping over long fibre or free-space links.
  1 EU-funded project · 1 organisation · 0 companies (0 SMEs) · 1 country · EU activity: low
  No company takes part in these projects.
  Quantum patent families (EPO): not checked yet for these companies.
  Title keywords: quantum repeater*, repeater node*, entanglement swapping, quantum network testbed*; counted only when the title also names the platform.
  Sources
  - Quantum memories: emerging applications and recent advances, Heshami et al., Journal of Modern Optics 63(20), 2005-2028 (Taylor & Francis), 2016. Sec. 1 (Introduction), second and third paragraphs; Sec. 2.3.2, first paragraph (repeaters at telecom wavelengths).

Sources

Each passage behind a part was read in the version linked as "read", and each DOI was resolved separately. Section numbers follow that version.

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Download the parts and their figures as JSON · European quantum supply chain in EU-funded projects · Patents, actors and a dated brief for one technology

Technology map of European quantum projects

Method and caveats

All parts as text

Superconducting circuits

Dilution refrigerator

Dilution unit and mixing chamber

Helium-3 and helium-4 mixture CRM

Pulse-tube cryocooler

Radiation and magnetic shielding

Qubit chip

Josephson junctions

Aluminium and aluminium oxide CRM SRM

Superconducting metal films

Aluminium CRM SRM

Niobium CRM

Tantalum CRM

Substrate

Silicon CRM SRM

Sapphire

Readout resonators and Purcell filters

Cryogenic signal lines

Coaxial cables

Niobium-titanium CRM SRM

Attenuators and filters

Circulators and isolators

Readout amplifier chain

Josephson parametric amplifiers

HEMT amplifiers

Room-temperature control electronics

Waveform generators and microwave sources

Readout mixers and digitisers

FPGA-based real-time control

Trapped ions

Ion trap

Surface-electrode trap chip

RF drive and electrode voltages

Atom source and photoionisation

Calcium

Ytterbium

Strontium CRM

Beryllium CRM

Magnesium CRM

Barium

Ultra-high-vacuum system

Vacuum chamber with optical windows

Cryogenic trap environment

Laser and optical control

Lasers at the atomic transition wavelengths

Acousto-optic modulators

Integrated light delivery

State detection

Collection optics

Photomultipliers, cameras and avalanche photodiodes

Superconducting nanowire detectors

Neutral atoms

Atomic register and vacuum system

Ultra-high-vacuum chamber

Rubidium

Magneto-optical trap

Optical tweezer array

Trapping laser

Spatial light modulator

Acousto-optic deflectors

High-numerical-aperture lenses

Processing lasers

Raman and Rydberg lasers

Acousto- and electro-optic modulators

Fluorescence imaging

EMCCD camera

Dichroic mirror

Control electronics and computing

FPGA and GPU rearrangement

Synthesisers and waveform generators

Photonic

Photon sources

Parametric photon-pair sources

Potassium titanyl phosphate (KTP)

Quantum-dot single-photon sources

Multiplexing switch networks

Integrated photonic circuits