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arXiv · 1905.05323

Two-stage Estimation for Quantum Detector Tomography: Error Analysis, Numerical and Experimental Results

Yuanlong Wang·Shota Yokoyama·Daoyi Dong·Ian R. Petersen·Elanor H. Huntington·Hidehiro Yonezawa
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Abstract

Quantum detector tomography is a fundamental technique for calibrating quantum devices and performing quantum engineering tasks. In this paper, a novel quantum detector tomography method is proposed. First, a series of different probe states are used to generate measurement data. Then, using constrained linear regression estimation, a stage-1 estimation of the detector is obtained. Finally, the positive semidefinite requirement is added to guarantee a physical stage-2 estimation. This Two-stage Estimation (TSE) method has computational complexity $O(nd^2M)$, where $n$ is the number of $d$-dimensional detector matrices and $M$ is the number of different probe states. An error upper bound is established, and optimization on the coherent probe states is investigated. We perform simulation and a quantum optical experiment to testify the effectiveness of the TSE method.

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Yuanlong Wang, Shota Yokoyama, Daoyi Dong, Ian R. Petersen, Elanor H. Huntington, Hidehiro Yonezawa. 2019-05-14. Two-stage Estimation for Quantum Detector Tomography: Error Analysis, Numerical and Experimental Results. https://doi.org/10.1109/tit.2021.3062596

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