Quantum Computing Research

⚠ Disclaimer: This section may contain incomplete, out of date, or inaccurate entries. It is AI-maintained on a best-effort basis. Do not rely on it as a sole source — verify claims independently using the source materials listed in individual entries.

Overview

Tracks the development of quantum computing hardware, software, and the race toward practical quantum advantage. The field spans multiple competing hardware modalities — superconducting circuits, trapped ions, photonics, and neutral atoms — each with distinct technical profiles and roadmap trajectories. Progress is real but slow relative to the projections routinely made by companies seeking funding and press coverage.

Editorial note: This section applies a higher skepticism standard than the rest of the Research knowledge base. Quantum computing is a field with a long history of aggressive roadmap claims, shifting definitions of success, and hype that has repeatedly outpaced demonstrated results. Claims about qubit counts, quantum advantage, and commercial timelines are documented with source dates and independent verification status.

Key Themes

  • Physical qubit counts are growing but error correction — the prerequisite for practical fault-tolerant computing — remains undemonstrated at useful scale
  • The gap between “quantum supremacy” demonstrations and commercial utility remains large; no real-world workload has shown verified advantage over optimized classical compute
  • Hardware modalities are diverging rather than converging: superconducting, trapped ion, photonic, and neutral atom approaches each have credible advocates and distinct engineering trade-offs
  • Microsoft’s topological qubit program has produced extraordinary claims but limited peer-reviewed validation
  • D-Wave occupies a distinct position as a quantum annealer, not a gate-based computer — its “quantum advantage” claims apply to a narrow problem class
  • Timeline compression is the norm in company communications; most published milestones have slipped by years

Companies

Startups & Development Partners

Company HQ Stage Mission
Rigetti Computing Berkeley, CA, USA Public (RGTI) Superconducting gate-based QPUs; Ankaa-3 (84 qubits, 99.5% median 2Q fidelity, company claim); Fab-1 in-house foundry (Fremont CA); cloud access via QCS, AWS Braket, Azure Quantum; financially stressed (revenue declining, $10.8M FY2024). See entry.
Xanadu Toronto, Canada Public (XNDU, Nasdaq/TSX; IPO Mar 2026) Photonic quantum computing; Borealis quantum advantage system; PennyLane open-source SDK; developing Aurora modular fault-tolerant platform; targeting 2028–2029 fault-tolerant data center. See entry.
PsiQuantum Palo Alto, CA, USA Private (~$7B val.; $2.32B raised) Silicon photonics fault-tolerant approach (FBQC); Omega chipset manufactured at GlobalFoundries Fab 8; A$940M AUD Australian government deal; $1B Series E (Sept 2025); Chicago site under construction; no operational quantum processor publicly demonstrated as of April 2026; DARPA QBI US2QC final phase selected (Feb 2025). See entry.
Quantinuum Broomfield, CO, USA + Cambridge, UK Private (~54% Honeywell; IPO targeted 2027) Trapped-ion hardware (H1, H2, Helios 98-qubit); highest two-qubit gate fidelity publicly demonstrated (99.921% on Helios); TKET open-source compiler; InQuanto chemistry; advanced fault-tolerant research. See entry.
D-Wave Quantum Burnaby, Canada Public (QBTS) Quantum annealing (not gate-based); Advantage2 (4,400+ qubits, Zephyr topology; GA Nov 2024); hybrid solvers on Leap cloud; 2025 quantum supremacy claim actively disputed; Jan 2026 acquisition of Quantum Circuits Inc. for gate-model entry. See entry.
IonQ College Park, MD, USA Public (IONQ) Trapped-ion gate-based systems; Forte and Forte Enterprise systems; #AQ metric contested. See entry.
SkyWater Technology Bloomington, MN, USA Public (SKYT; pending IonQ acquisition) U.S. pure-play semiconductor foundry; DOD Trusted Foundry; fabricates superconducting qubits (D-Wave), photonics; pending $1.8B IonQ acquisition (expected Q2–Q3 2026). See entry.

Public Companies

Ticker Company Mission
XNDU Xanadu Photonic quantum computing hardware; Borealis quantum advantage system; Aurora modular fault-tolerant platform; PennyLane open-source SDK. See entry.
IONQ IonQ Trapped-ion quantum computing hardware and cloud access; Forte (#AQ 36) and Tempo (#AQ 64) systems; pending SkyWater foundry acquisition. See entry.
SKYT SkyWater Technology U.S. pure-play semiconductor foundry; DOD Trusted Foundry; quantum chip fabrication (superconducting, photonic, cryogenic CMOS); pending IonQ acquisition. See entry.
QBTS D-Wave Quantum Quantum annealing systems (not gate-based) and hybrid classical-quantum solvers; Advantage2 (4,400+ qubits, Zephyr); 2025 Science quantum supremacy paper disputed by independent teams; acquiring Quantum Circuits Inc. for gate-model entry. See entry.
RGTI Rigetti Computing Superconducting gate-based QPUs manufactured at Fab-1 (Fremont, CA); Ankaa-3 84-qubit system (99.5% median 2Q fidelity, company claim); cloud access via QCS, AWS Braket, Azure Quantum; FY2024 revenue $10.8M (declining); $217M cash (Dec 2024); DARPA QBI Stage A (not Stage B). See entry.

Incumbents

Ticker Company Relevance
IBM IBM Quantum Largest publicly accessible quantum fleet; superconducting QPUs (Eagle, Heron, Nighthawk, Loon); qLDPC error correction research; 2029 Starling and 2033 Blue Jay fault-tolerant roadmap. See entry.
MSFT Microsoft Azure Quantum Topological qubit research (majorana); Azure Quantum cloud platform; claims disputed.
GOOGL Google Quantum AI Superconducting QPUs (Sycamore 53-qubit, Willow 105-qubit); 2019 supremacy claim (classically matched 2024); Willow 2024 below-threshold error correction (partially verified); dual-modality expansion to neutral atoms (March 2026); 2029 fault-tolerant target. See entry.

Entries

  • D-Wave Quantum — D-Wave (NYSE: QBTS) makes quantum annealers — not gate-based quantum computers. Its Advantage2 processor uses analog optimization for combinatorial problems. Quantum advantage claims are actively disputed by independent researchers.
  • Google Quantum AI — Google's superconducting quantum computing program; Sycamore 2019 supremacy claim (contested), Willow 2024 below-threshold error correction (partially verified), dual-modality expansion to neutral atoms (March 2026); targeting useful fault-tolerant quantum computer by 2029.
  • IBM Quantum — Largest publicly accessible quantum computing fleet; superconducting QPU modality; Eagle, Heron, Nighthawk, and Loon processors on roadmap; 2029 Starling fault-tolerant target; qLDPC error correction research; cloud access via IBM Quantum Platform and Qiskit SDK.
  • IonQ — Publicly traded trapped-ion quantum computing company; produces Forte and Tempo systems; uses ytterbium ions as qubits; cloud access via AWS, Azure, and Google Cloud.
  • PsiQuantum — Silicon photonics quantum computing startup pursuing fault-tolerant photonic computing by manufacturing integrated chipsets at GlobalFoundries; the most heavily funded independent quantum hardware company with no publicly demonstrated quantum processor as of early 2026.
  • Quantinuum — Privately held trapped-ion quantum computing company formed by the 2021 merger of Honeywell Quantum Solutions and Cambridge Quantum; produces the H-series (H1, H2) and Helios systems; holds the highest publicly demonstrated two-qubit gate fidelity of any commercial system.
  • Rigetti Computing — Publicly traded superconducting quantum computing company; builds QPUs at its own Fab-1 foundry; sells cloud access via QCS, AWS Braket, and Azure Quantum; financially stressed with declining revenue.
  • SkyWater Technology — U.S. pure-play semiconductor foundry serving defense, commercial, and quantum computing customers; pending acquisition by IonQ; fabricates superconducting qubits for D-Wave, photonic chips for PsiQuantum (prior to GlobalFoundries transition), and cryogenic control electronics.
  • Xanadu — Toronto-based photonic quantum computing company; developed Borealis quantum advantage system and PennyLane open-source SDK; recently went public via SPAC merger; building Aurora modular fault-tolerant platform targeting 2028–2029 deployment.