Rigetti Computing has put its 108-qubit Cepheus-1-108Q system into general availability, tripling the qubit count of its prior 36-qubit Cepheus-1-36Q platform and making it the company’s largest modular quantum system to date.
The new system is built from 12 interconnected 9-qubit chiplets. Rigetti said Cepheus-1-108Q is now available through its Quantum Cloud Services platform and via Amazon Braket.
At launch, the system is running at a 99.1% median two-qubit gate fidelity, a 99.9% median single-gate fidelity, and a gate speed of about 60 nanoseconds. Rigetti said it expects the median two-qubit gate fidelity to improve to 99.5% later this year.
The company also said it has already demonstrated a two-qubit gate fidelity as high as 99.9% at 28 nanoseconds on a prototype system using an adiabatic CZ gate scheme, and those gates are now in use on Cepheus-1-108Q.
Rigetti said the new system includes upgraded control electronics, a redesigned qubit and coupler architecture, and an advanced fabrication process using alternating-bias assisted annealing. During development, the company said it reduced coupling interactions between tunable couplers that become more difficult to manage above 100 qubits.
The launch follows Rigetti’s earlier 36-qubit Cepheus-1 system, meaning the company has moved from 36 qubits to 108 qubits in its latest platform generation. Rigetti said it will continue improving system performance through 2026 as it pushes to higher qubit counts. Today the company's shares have moved -4.82% to a price of $14.41. For more information, read the company's full 8-K submission here.
