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arXiv · 2108.10431

Theory of mirror benchmarking and demonstration on a quantum computer

Karl Mayer·Alex Hall·Thomas Gatterman·Si Khadir Halit·Kenny Lee·Justin Bohnet·Dan Gresh·Aaron Hankin·Kevin Gilmore·Justin Gerber·John Gaebler
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Abstract

A new class of protocols called mirror benchmarking was recently proposed to measure the system-level performance of quantum computers. These protocols involve circuits with random sequences of gates followed by mirroring, that is, inverting each gate in the sequence. We give a simple proof that mirror benchmarking leads to an exponential decay of the survival probability with sequence length, under the uniform noise assumption, provided the twirling group forms a 2-design. The decay rate is determined by a quantity that is a quadratic function of the error channel, and for certain types of errors is equal to the unitarity. This result yields a new method for estimating the coherence of noise. We present data from mirror benchmarking experiments run on the Honeywell System Model H1. This data constitutes a set of performance curves, indicating the success probability for random circuits as a function of qubit number and circuit depth.

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Karl Mayer, Alex Hall, Thomas Gatterman, Si Khadir Halit, Kenny Lee, Justin Bohnet, Dan Gresh, Aaron Hankin, Kevin Gilmore, Justin Gerber, John Gaebler. 2021-08-23. Theory of mirror benchmarking and demonstration on a quantum computer. https://arxiv.org/abs/2108.10431

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