Bosonic GKP Error-Corrected Qubits by Nord Quantique: status and timeline

Bosonic GKP Error-Corrected Qubits

GKP bosonic codes in superconducting cavities for fault-tolerant quantum computing. Uses 1:1 logical-to-physical qubits, avoiding the overhead of traditional approaches.

ProtoStage 2 of 5

DARPA Stage B; sub-0.1% SPAM errors demonstrated; targeting four-qubit gate system.

Updated Jul 2026Checked 10 Oct0 updates this week

Milestones

Next · Four-qubit gate system operational

Founded, emerges from Institut Quantique2020Complete.
Seed funding round announcedFeb 2022Complete.
Advances to DARPA QBI Stage B2025Complete.
Demonstrates first Tesseract multimodal codesMay 2025Complete.
SPAM errors suppressed below 0.1%Jul 2026Complete.
Four-qubit gate system operationalTarget 2026Current milestone.

Most important updates

Nord Quantique demonstrates SPAM errors below 0.1% in GKP bosonic qubitsJul 2026

Upcoming

2026Four-qubit gate system operational (next)
2027Error correction demonstration at logical qubit scale

Current obstacles

Scaling cavity systemsConnecting multiple cavities without crosstalk and decoherence becomes harder as system size grows.
Readout fidelityGrid-state qubits require precision homodyne detection; improving readout fidelity while supporting autonomous correction is challenging.

Physics limits

Cavity quality factor limits coherenceSuperconducting resonator quality (Q) sets coherence time; reducing losses from coupling and control electronics is difficult.
Cryogenic infrastructure costScaling to thousands of cavities requires larger dilution refrigerators and cryogenic systems, raising costs significantly.

How it works

3 parts

GKP codes

Grid state codes in cavities

GKP codes use superconducting resonators' large Hilbert space to store quantum information in grid patterns, encoding multiple qubits per cavity.

Correction

Autonomous error detection

Cavity resonators support autonomous error correction that detects and suppresses errors in real time without collapsing the quantum state.

Efficiency

1:1 logical-to-physical ratio

Embeds error correction directly in hardware, avoiding the thousands-to-one overhead of conventional superconducting approaches.

Spec sheet

Spec	Bosonic GKP Error-Corrected Qubits
SPAM error rate (2026)	<0.1%^R (reported)
Single-qubit gate fidelity target	>99.9%^E (estimated)
Logical-to-physical qubit ratio	1:1^R (reported)
Target cryostat footprint	10 m²^R (reported)

^R reported by the company · ^E our estimate

Papers & demos

1 item

Jul 2025demo
SPAM errors below 0.1% in GKP qubits (opens quantumcomputingreport.com)Hundredfold improvement in error suppression for fault-tolerant quantum computing.

Update log

1 update

Jul 2026

Major: Nord Quantique demonstrates SPAM errors below 0.1% in GKP bosonic qubitsPressHardware

About Nord Quantique

The team behind Bosonic GKP Error-Corrected Qubits

Nord Quantique

Bosonic GKP qubits, error-corrected quantum computers

Nord Quantique builds fault-tolerant quantum computers using superconducting bosonic codes with 1:1 logical-to-physical qubits. Founded in 2020 from the Institut Quantique, it is advancing DARPA's quantum research with a $1.4B valuation.

Targets 1:1 logical-to-physical qubit ratio by embedding error correction in hardware.
Advanced to DARPA's Quantum Benchmarking Initiative Stage B alongside ten other global leaders.
Demonstrated SPAM errors below 0.1% in GKP bosonic qubits, a hundredfold advance.

nordquantique.com (opens nordquantique.com)Company profile →

Founded: 20206 yrs
Headquarters: Canada
Status: Private
Valuation: $1.4BprivateMay 2026
Raised: $38M2 rounds
Last round: Series A · $30MMay 2026
Works in: QuantumSuperconducting
Coverage: 1 program · 4 updateslatest 1 Jul 2026checked 10 Oct
Partners: DARPA Quantum Benchmarking Initiative (opens darpa.mil)Institut Quantique (opens usherbrooke.ca)
People: Julien Camirand Lemyre (opens deep-tech-week.com)Co-founder & CEOPhilippe St-Jean (opens nordquantique.com)Co-founder

Spec

Bosonic GKP Error-Corrected Qubits

SPAM error rate (2026)

<0.1%^R (reported)

Single-qubit gate fidelity target

>99.9%^E (estimated)

Logical-to-physical qubit ratio

1:1^R (reported)

Target cryostat footprint

10 m²^R (reported)