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arXiv · 2111.11937

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

A. R. Mills·C. R. Guinn·M. J. Gullans·A. J. Sigillito·M. M. Feldman·E. Nielsen·J. R. Petta
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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 over 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.

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A. R. Mills, C. R. Guinn, M. J. Gullans, A. J. Sigillito, M. M. Feldman, E. Nielsen, J. R. Petta. 2021-11-23. Two-qubit silicon quantum processor with operation fidelity exceeding 99%. https://doi.org/10.1126/sciadv.abn5130

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