Rigetti roadmap update: Cepheus-1-108Q System Launch Status
Strategic Timeline Update for 108-Qubit Cepheus System by Rigetti Computing
Cepheus-1-108Q
Rigetti Computing, Inc., a pioneer in full-stack quantum-classical computing research, amended its technical roadmap and changed the launch date for the anticipated Cepheus-1-108Q system. Berkeley-based business says 108-qubit quantum computing gadget will be available by first quarter 2026. This move reflects the company's focus on performance and reliability of its largest modular system.
High-fidelity performance optimization
Rigetti changed the roadmap to meet a 99.5% median two-qubit gate fidelity performance goal. The company is making “strong progress,” but CEO Dr. Subodh Kulkarni says it is spending more time testing and improving the technology to meet internal criteria.
Rigetti has achieved notable achievements across its fleet with a 99% median two-qubit gate fidelity on the 108-qubit system. The 36-qubit and 9-qubit business systems are considerably more precise, reaching 99.6% and 99.7%, respectively. These results show an industry issue: maintaining high quality becomes more harder as qubit counts climb.
Technology Challenges: Chip Evolution and Flexible Connections
The transition to 108 qubits has created new engineering hurdles. When building systems with additional qubits, Dr. Kulkarni often encounters issues with adjustable couplers. Rigetti has upgraded their CPU to fix these issues and improve system fidelity.
Strength of Modular Architecture
The Cepheus-1-108Q uses Rigetti's modular chip design instead of a monolithic processor. The system uses twelve tiled 9-qubit chiplets. This modular approach underpins Rigetti's scaling method. The first large-scale demonstration of Cepheus-1-36Q, which used four 9-qubit chiplets, occurred in 2025.
This multi-chip technology lets Rigetti build the largest modular quantum computing system. The company's Fab-1 facility, the first integrated quantum device production factory, can make tiny, high-performance “chiplets” that can be built into bigger processors.
Speed and edge
Rigetti still supports superconducting qubits as the most promising modality due to their maturity and scaling method. Speed is a major benefit of this technology. The company claims that Rigetti systems have gate speeds of 50–70ns, 1,000 times faster than ion traps or neutral atoms.
The speed needed for “full-stack” performance allows quantum algorithms to run faster and interface more closely with standard computing infrastructure. International industry and government clients benefit from the company's proprietary quantum-classical architecture's high-performance integration with public and private clouds.
Market supply and availability
Rigetti serves many clients once the 108-qubit system's timeframe modified. The company runs its hardware on Rigetti Quantum Cloud Services (QCS), which allows remote R&D.
Rigetti offers 9–108 qubit on-premises systems for national labs and quantum computing facilities. Designed for the R&D community, their 9-qubit Novera QPU is a high-performance chip that can be integrated into control and cryogenic systems.
Looking Ahead
While pursuing the new Q1 2026 goal, Rigetti faces normal sector risks like supply chain stability, inflation, government contracts, and technology developments. The management's “unwavering commitment” to providing partners with high-performance equipment remains their top focus.
Rigetti believes the 36-qubit Cepheus-1 to 108-qubit Cepheus-1-108Q capacity tripling will allow users to investigate more complex real-world quantum computing applications.
