Technology / Hardware / Photonic
Photonic
Single photons and optical modes.
The tradeoff
Strengths: Room-temperature transmission; Networking potential.
Challenges: Photon loss; Deterministic sources; Detectors; Large overhead.
Maturity: prototype; betting on a leap to fault tolerance.
Specific gate speeds, fidelities and qubit counts are not published here, they change quarterly. Verify against each company's latest technical publications, not press releases.
Who is pursuing it
PsiQuantum
The best-funded private quantum company; skipping NISQ entirely to build a million-qubit fault-tolerant photonic machine using semiconductor fabs.
private
Xanadu
Canadian photonic company behind the PennyLane software library and photonic sampling demonstrations.
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Quandela
French photonic company building single-photon sources and cloud-accessible photonic processors.
private
ORCA Computing
UK photonic company using fiber-based memory to make photonic processing practical at room temperature.
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