Those wishing to hone their quantum computer programming skills had the opportunity to work on the latest platform of the Californian startup Rigetti Computing. The company has opened cloud access to an 84-qubit system on the latest Ankaa-3 processor. The Rigetti platform uses classical superconducting qubits, which could make its new platform the most popular among users.
Quantum processor and computer from Rigetti Computing. Image source: Rigetti Computing
According to Rigetti, thanks to the modernized architecture, the accuracy of quantum gates is significantly increased, which leads to more reliable calculation results. In particular, in 2024, it was possible to halve the error rate and achieve an average accuracy of iSWAP gates at 99.0%, and also demonstrate an average accuracy of fSim gates at 99.5%. The average execution time for iSWAP elements was 72 ns, and for fSim it was 56 ns. The company calls fSim gates optimized for sampling random circuits, making them similar to Google’s quantum chips and its latest Willow processor.
Rigetti has improved not only the qubit architecture, but also modernized the entire quantum processor manufacturing chain, from methods of metallizing individual elements such as superconducting Josephson junctions to organizing qubits into arrays for error correction. Rigetti qubits are Josephson junctions, resonators and radio frequency sensors that are cooled as part of the platform to just above absolute zero (about 10 mK). To produce such qubits, an adapted microelectromechanical systems (MEMS) manufacturing process is used, well known in the semiconductor industry.
The company plans to introduce the next generation of its quantum modular architecture in 2024. For example, closer to summer there will be a 36-qubit system based on four 9-qubit chips connected together. This will reduce the error rate by half compared to the current level. By the end of 2025, Rigetti plans to release a system with more than 100 qubits, which will also lead to a twofold reduction in error rates compared to today.
In addition, Rigetti Computing will soon provide cloud access to its latest 84-qubit computer through third-party platforms such as Amazon Braket and Microsoft Azure.