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Two-qubit silicon quantum processor with operation fidelity exceeding 99.

ABSTRACT: Silicon spin qubits satisfy the necessary criteria for quantum information processing. However, a demonstration of high-fidelity state preparation and readout combined with high-fidelity single- and two-qubit gates, all of which must be present for quantum error correction, has been lacking. We use a two-qubit Si/SiGe quantum processor to demonstrate state preparation and readout with fidelity greater than 97%, combined with both single- and two-qubit control fidelities exceeding 99%. The operation of the quantum processor is quantitatively characterized using gate set tomography and randomized benchmarking. Our results highlight the potential of silicon spin qubits to become a dominant technology in the development of intermediate-scale quantum processors.

SUBMITTER: Mills AR

PROVIDER: S-EPMC8986105 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature

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Two-qubit silicon quantum processor with operation fidelity exceeding 99.

Mills Adam R AR Guinn Charles R CR Gullans Michael J MJ Sigillito Anthony J AJ Feldman Mayer M MM Nielsen Erik E Petta Jason R JR

Science advances 20220406 14

Silicon spin qubits satisfy the necessary criteria for quantum information processing. However, a demonstration of high-fidelity state preparation and readout combined with high-fidelity single- and two-qubit gates, all of which must be present for quantum error correction, has been lacking. We use a two-qubit Si/SiGe quantum processor to demonstrate state preparation and readout with fidelity greater than 97%, combined with both single- and two-qubit control fidelities exceeding 99%. The operat ...[more]

PMID: 35385308

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