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arXiv · 1510.02720

Scalable randomized benchmarking of non-Clifford gates

Andrew W. Cross·Easwar Magesan·Lev S. Bishop·John A. Smolin·Jay M. Gambetta
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Abstract

Randomized benchmarking is a widely used experimental technique to characterize the average error of quantum operations. Benchmarking procedures that scale to enable characterization of $n$-qubit circuits rely on efficient procedures for manipulating those circuits and, as such, have been limited to subgroups of the Clifford group. However, universal quantum computers require additional, non-Clifford gates to approximate arbitrary unitary transformations. We define a scalable randomized benchmarking procedure over $n$-qubit unitary matrices that correspond to protected non-Clifford gates for a class of stabilizer codes. We present efficient methods for representing and composing group elements, sampling them uniformly, and synthesizing corresponding $\mathrm{poly}(n)$-sized circuits. The procedure provides experimental access to two independent parameters that together characterize the average gate fidelity of a group element.

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Andrew W. Cross, Easwar Magesan, Lev S. Bishop, John A. Smolin, Jay M. Gambetta. 2015-10-09. Scalable randomized benchmarking of non-Clifford gates. https://doi.org/10.1038/npjqi.2016.12

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