IBM announced at CES 2020 that its newest 28-qubit quantum computer, Raleigh, achieved the company’s goal of doubling its Quantum Volume (IBM names its systems by city names). Raleigh reached a Quantum Volume of 32 this year, up from 16 last year. Raleigh draws on an improved hexagonal lattice connectivity structure developed in IBM’s 53-qubit quantum computer, and features improved coherence aspects. According to IBM, the lattice connectivity had an impact on reduced gate errors and exposure to crosstalk.
Quantum Volume is a full-system architecture-independent quantum computer performance metric developed by IBM researchers in 2017. Quantum Volume considers such technical factors as how long qubits can maintain their quantum state, errors made during hardware calibration, noise, crosstalk, spectator errors, gate fidelity and other fidelity measurements. It also considers the number of qubits and their connectivity, as well as circuit software compiler efficiency.
Some circuit-based quantum computer companies, like Rigetti, have reported results, while many have remained silent for various reasons.
IBM prefers speaking of Quantum Advantage, instead of Quantum Supremacy. (Forbes)
