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Vol. III·Sector Directory·Companies
41 names · listed & material private
Boulder · Colorado
updated continuously

The quantum cohort

A screener for the quantum economy — every public ticker and material private actor, ranked by the Ledger Score and read against the same set of editorial questions.

The most useful screener for a pre-revenue sector is the one that lets you sort by conviction, not market cap.

— the editorial premise of this directory

The cohort below is the universe the Ledger watches every weekday. It is curated, not exhaustive: each name is here because it is either publicly listed, materially funded, or carrying a technical claim other operators take seriously. The Ledger Score is a composite — capital, technical milestones, sentiment, policy, talent, patents — and is not a recommendation. Treat the rankings as a starting point, the per-company profile as the actual argument.

Filter by ownership=private, modality=all, or change the sort order=score. The directory state lives in the URL — copy the address bar and you've shared the screen.

Most active · today's session

Where the cohort is moving

INFQ-11.0%

Most-diversified quantum portfolio — neutral atom computer + atomic clocks + sensors; only US-listed neutral-atom pure-play.

Neutral atomBoulder, CO, USA
QUBT-10.4%

A $1.4B cash hoard from peak-retail ATM raises looking for a thesis — photonic chip foundry + post-quantum crypto via NuCrypt.

PhotonicHoboken, NJ, USA
IONQ-9.6%

The only public quantum pure-play crossing $100M revenue; vertically integrating via the $1.8B SkyWater acquisition.

Trapped ionCollege Park, MD, USA

The screener · 30 of 41 match

Ranked by Ledger conviction

Ownership
AllListedPrivate
Modality
All modalitiesSuperconductingTrapped ionNeutral atomPhotonicSilicon spinAnnealingTopologicalSoftware & QEC
Sort
Ledger ScoreMarket capΔ sessionA–Z
  1. 01
    QuantinuumPRIVATEPrivate

    Highest-fidelity trapped-ion stack in commercial production; S-1 filed May 8 2026 targeting $20B+ IPO under ticker QNT.

    Trapped ion

    Broomfield, CO / Cambridge, USA/UK

    n/a
    n/a
    78/100
  2. 02
    SandboxAQPRIVATEPrivate

    Alphabet spinoff selling "Large Quantitative Models" for materials/drug discovery/PQC; highest-valued private quantum-adjacent company.

    Software / QEC

    Palo Alto, CA, USA

    n/a
    n/a
    73/100
  3. 03
    PsiQuantumPRIVATEPrivate

    Most ambitious bet in the field — utility-scale photonic FTQC with sovereign backing (US + Australia); Brisbane facility online 2027.

    Photonic

    Palo Alto, CA, USA

    n/a
    n/a
    72/100
  4. 04
    IQM Quantum ComputersPRIVATEPrivate

    Largest European on-prem quantum installer; 15 systems shipped to HPC centers; €275M Series B was the largest in industry history.

    Superconducting

    Espoo, Finland

    n/a
    n/a
    70/100
  5. 05
    RiverlanePRIVATEPrivate

    Hardware-agnostic Quantum Error Correction stack (Deltaflow); the picks-and-shovels QEC layer used by >60% of quantum hardware companies.

    qec_stack

    Cambridge, UK

    n/a
    n/a
    70/100
  6. 06
    Quantum MachinesPRIVATEPrivate

    OPX/OPX1000 quantum control platform — the de facto infrastructure used by >50% of all quantum hardware vendors.

    controls

    Tel Aviv, Israel

    n/a
    n/a
    69/100
  7. 07
    Q-CTRLPRIVATEPrivate

    Quantum control software + quantum sensing for defense PNT — only quantum-software company with material defense sensing revenue.

    controls

    Sydney, Australia

    n/a
    n/a
    68/100
  8. 08
    PasqalPRIVATEPrivate

    European neutral-atom champion; SPAC merger announced March 2026 at $2.6B pro forma — second public neutral-atom name after Xanadu.

    Neutral atom

    Massy, France

    n/a
    n/a
    65/100
  9. 09
    Atom ComputingPRIVATEPrivate

    Neutral-atom contender deeply embedded with Microsoft; jointly set the 24-logical-qubit record.

    Neutral atom

    Boulder, CO, USA

    n/a
    n/a
    63/100
  10. 10
    Multiverse ComputingPRIVATEPrivate

    Tensor-network methods pivoted to CompactifAI — highest ARR of any "quantum" company, though the quantum link is now thin.

    Software / QEC

    San Sebastián, Spain

    n/a
    n/a
    63/100
  11. 11
    QuEra ComputingPRIVATEPrivate

    Harvard/MIT-pedigree neutral-atom company with strongest published logical-qubit results; Google + SoftBank backing.

    Neutral atom

    Boston, MA, USA

    n/a
    n/a
    62/100
  12. 12
    Quantum MotionPRIVATEPrivate

    Full-stack silicon CMOS spin qubits manufactured in standard foundries — closest path to leveraging $500B semiconductor capex.

    Silicon spin

    London, UK

    n/a
    n/a
    61/100
  13. 13
    Photonic Inc.PRIVATEPrivate

    Silicon T-centre spin-photon interface for distributed quantum — the most architecturally novel QBI Stage B bet, Microsoft-backed.

    Silicon spin

    Vancouver, BC, Canada

    n/a
    n/a
    60/100
  14. 14
    Origin QuantumPRIVATEPrivate

    China's national quantum champion — only Chinese company with a complete vertical stack; STAR Market IPO in counseling.

    Superconducting

    Hefei, China

    n/a
    n/a
    56/100
  15. 15
    Nord QuantiquePRIVATEPrivate

    Multi-mode bosonic qubits claiming a 1:1 physical-to-logical ratio — the highest-asymmetry bet in DARPA QBI Stage B.

    Bosonic

    Sherbrooke, QC, Canada

    n/a
    n/a
    53/100
  16. 16
    DiraqPRIVATEPrivate

    Silicon-spin frontrunner — industrial-CMOS-compatible qubits at >99% two-qubit fidelity; the manufacturing-thesis dark horse.

    Silicon spin

    Sydney, Australia

    n/a
    n/a
    52/100
  17. 17
    ClassiqPRIVATEPrivate

    High-level quantum algorithm-design platform — the "Microsoft of quantum" with broadest enterprise customer book; AMD/Qualcomm/IonQ strategic investors.

    Software / QEC

    Tel Aviv, Israel

    n/a
    n/a
    52/100
  18. 18
    Silicon Quantum ComputingPRIVATEPrivate

    Atom-by-atom precision-placed donor qubits in silicon via STM lithography — Michelle Simmons team, 20-year head start on the modality.

    Silicon spin

    Sydney, Australia

    n/a
    n/a
    47/100
  19. 19
    QuandelaPRIVATEPrivate

    French photonic pure-play with deterministic single-photon sources; "Lucy" 12-qubit computer delivered to CEA TGCC under EuroQCS-France.

    Photonic

    Massy, France

    n/a
    n/a
    47/100
  20. 20
    Alice & BobPRIVATEPrivate

    Cat-qubit pioneer claiming 100× hardware-efficiency thesis; Boson 4 chip achieved >7-minute bit-flip lifetime (world record).

    Cat qubit

    Paris, France

    n/a
    n/a
    46/100
  21. 21
    Quantum BrilliancePRIVATEPrivate

    Room-temperature NV-diamond quantum accelerators — only credible rack-mountable quantum for edge/defense/satellite use cases.

    NV-diamond sensing

    Canberra / Stuttgart, Australia/Germany

    n/a
    n/a
    42/100
  22. 22
    QuoblyPRIVATEPrivate

    CEA-Leti silicon spin-qubit spinout — French sovereign bet on FD-SOI 300mm manufacturing scale.

    Silicon spin

    Grenoble, France

    n/a
    n/a
    40/100
  23. 23
    Quantum SourcePRIVATEPrivate

    Photonic FTQC bet on the ORIGIN deterministic-photon source — designed to avoid PsiQuantum's probabilistic-gate overhead.

    Photonic

    Rehovot, Israel

    n/a
    n/a
    36/100
  24. 24
    Zapata QuantumPRIVATEPrivate

    Post-bankruptcy revival of the original quantum-software pioneer — needs at least two more quarters of revenue evidence before it's investable.

    Software / QEC

    Boston, MA, USA

    n/a
    n/a
    27/100
  25. 25
    Universal QuantumPRIVATEPrivate

    UK trapped-ion company building toward one-million-qubit modular architecture via silicon-chip-based ion traps and electric-field qubit transport — distinct from QCCD shuttling.

    Trapped ion

    Brighton, UK

    n/a
    n/a
    0/100
  26. 26
    Alpine Quantum Technologies (AQT)PRIVATEPrivate

    Austrian Innsbruck-physics-lab spinout (Rainer Blatt) building rack-mounted commercial ion traps — the only true "quantum computer in a box" product on the market.

    Trapped ion

    Innsbruck, Austria

    n/a
    n/a
    0/100
  27. 27
    AlgorithmiqPRIVATEPrivate

    Most-funded quantum drug discovery software company — pivoting from generic chemistry to clinical pharma partnerships.

    Software / QEC

    Helsinki, Finland

    n/a
    n/a
    0/100
  28. 28
    Quix QuantumPRIVATEPrivate

    Dutch photonic processor company specializing in low-loss silicon-nitride waveguide chips — the highest-performing commercial photonic quantum hardware available off the shelf.

    Photonic

    Enschede, Netherlands

    n/a
    n/a
    0/100
  29. 29
    ORCA ComputingPRIVATEPrivate

    UK photonic company building room-temperature photonic systems for quantum-classical hybrid AI workloads.

    Photonic

    London, UK

    n/a
    n/a
    0/100
  30. 30
    Cerca MagneticsPRIVATEPrivate

    Largest commercial OPM (optically-pumped magnetometer) sensor company — the dominant supplier in next-generation MEG brain imaging.

    NV-diamond sensing

    Nottingham, UK

    n/a
    n/a
    0/100

A cohort is not an index. We omit names that publish only aspirational roadmaps; we include names with no revenue if a sovereign technical buyer has audited the science.

— directory methodology

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