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arXiv · 1210.7011

Process verification of two-qubit quantum gates by randomized benchmarking

A. D. Córcoles·Jay M. Gambetta·Jerry M. Chow·John A. Smolin·Matthew Ware·J. D. Strand·B. L. T. Plourde·M. Steffen
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Abstract

We implement a complete randomized benchmarking protocol on a system of two superconducting qubits. The protocol consists of randomizing over gates in the Clifford group, which experimentally are generated via an improved two-qubit cross-resonance gate implementation and single-qubit unitaries. From this we extract an optimal average error per Clifford of 0.0936. We also perform an interleaved experiment, alternating our optimal two-qubit gate with random two-qubit Clifford gates, to obtain a two-qubit gate error of 0.0653. We compare these values with a two-qubit gate error of ~0.12 obtained from quantum process tomography, which is likely limited by state preparation and measurement errors.

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A. D. Córcoles, Jay M. Gambetta, Jerry M. Chow, John A. Smolin, Matthew Ware, J. D. Strand, B. L. T. Plourde, M. Steffen. 2012-11-02. Process verification of two-qubit quantum gates by randomized benchmarking. https://doi.org/10.1103/physreva.87.030301

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