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arXiv · 2302.09823

Ultimate precision limit of SU(2) and SU(1,1) interferometers in noisy metrology

Jie Zeng·Dong Li·L. Q. Chen·Weiping Zhang·Chun-Hua Yuan
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Abstract

The quantum Fisher information (QFI) in SU(2) and SU(1,1) interferometers was considered, and the QFI-only calculation was overestimated. In general, the phase estimation as a two-parameter estimation problem, and the quantum Fisher information matrix (QFIM) is necessary. In this paper, we theoretically generalize the model developed by Escher et al [Nature Physics 7, 406 (2011)] to the QFIM case with noise and study the ultimate precision limits of SU(2) and SU(1,1) interferometers with photon losses because photon losses as a very usual noise may happen to the phase measurement process. Using coherent state and squeezed vacuum state as a specific example, we numerically analyze the variation of the overestimated QFI with the loss coefficient, and find its disappearance and recovery phenomenon.

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Jie Zeng, Dong Li, L. Q. Chen, Weiping Zhang, Chun-Hua Yuan. 2023-02-20. Ultimate precision limit of SU(2) and SU(1,1) interferometers in noisy metrology. https://arxiv.org/abs/2302.09823

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