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arXiv · 2003.02354

Correlated Randomized Benchmarking

David C. McKay·Andrew W. Cross·Christopher J. Wood·Jay M. Gambetta
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Abstract

To improve the performance of multi-qubit algorithms on quantum devices it is critical to have methods for characterizing non-local quantum errors such as crosstalk. To address this issue, we propose and test an extension to the analysis of simultaneous randomized benchmarking data -- correlated randomized benchmarking. We fit the decay of correlated polarizations to a composition of fixed-weight depolarizing maps to characterize the locality and weight of crosstalk errors. From these errors we introduce a crosstalk metric which indicates the distance to the closest map with only local errors. We demonstrate this technique experimentally with a four-qubit superconducting device and utilize correlated RB to validate crosstalk reduction when we implement an echo sequence.

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David C. McKay, Andrew W. Cross, Christopher J. Wood, Jay M. Gambetta. 2020-03-04. Correlated Randomized Benchmarking. https://arxiv.org/abs/2003.02354

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