Enhanced estimation of quantum properties with common randomized measurements

• URL: http://arxiv.org/abs/2304.12292v1
• Date: Mon, 24 Apr 2023 17:44:31 GMT
• Title: Enhanced estimation of quantum properties with common randomized measurements
• Authors: Beno\^it Vermersch, Aniket Rath, Bharathan Sundar, Cyril Branciard, John Preskill, Andreas Elben
• Abstract summary: We present a technique for enhancing the estimation of quantum state properties by incorporating approximate prior knowledge about the quantum state of interest. This method involves performing randomized measurements on a quantum processor and comparing the results with those obtained from a classical computer that stores an approximation of the quantum state.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We present a technique for enhancing the estimation of quantum state properties by incorporating approximate prior knowledge about the quantum state of interest. This method involves performing randomized measurements on a quantum processor and comparing the results with those obtained from a classical computer that stores an approximation of the quantum state. We provide unbiased estimators for expectation values of multi-copy observables and present performance guarantees in terms of variance bounds which depend on the prior knowledge accuracy. We demonstrate the effectiveness of our approach through numerical experiments estimating polynomial approximations of the von Neumann entropy and quantum state fidelities.

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