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arXiv · 1608.02943

Estimating the fidelity of T gates using standard interleaved randomized benchmarking

Robin Harper·Steven T. Flammia
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Abstract

Randomized benchmarking (RB) is an important protocol for robustly characterizing the error rates of quantum gates. The technique is typically applied to the Clifford gates since they form a group that satisfies a convenient technical condition of forming a unitary 2-design, in addition to having a tight connection to fault-tolerant quantum computing and an efficient classical simulation. In order to achieve universal quantum computing one must add at least one additional gate such as the T gate (also known as the $\pi$/8 gate). Here we propose and analyze a simple variation of the standard interleaved RB protocol that can accurately estimate the average fidelity of the T gate while retaining the many advantages of a unitary 2-design and the fidelity guarantees that such a design delivers, as well as the efficient classical simulation property of the Clifford group. Our work complements prior methods that have succeeded in estimating T gate fidelities, but only by relaxing the 2-design constraint and using a more complicated data analysis.

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Robin Harper, Steven T. Flammia. 2016-08-09. Estimating the fidelity of T gates using standard interleaved randomized benchmarking. https://doi.org/10.1088/2058-9565%2Faa5f8d

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