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arXiv · 2407.13433

Precision bounds for quantum phase estimation using two-mode squeezed Gaussian states

Jian-Dong Zhang·Chuang Li·Lili Hou·Shuai Wang
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Abstract

Quantum phase estimation based on Gaussian states plays a crucial role in many application fields. In this paper, we study the precision bound for the scheme using two-mode squeezed Gaussian states. The quantum Fisher information is calculated and its maximization is used to determine the optimal parameters. We find that two single-mode squeezed vacuum states are the optimal inputs and the corresponding precision bound is superior to the Heisenberg limit by a factor of 2. For practical purposes, we consider the effects originating from photon loss. The precision bound can still outperform the shot-noise limit when the lossy rate is below 0.4. Our work may demonstrate a significant and promising step towards practical quantum metrology.

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Jian-Dong Zhang, Chuang Li, Lili Hou, Shuai Wang. 2024-07-18. Precision bounds for quantum phase estimation using two-mode squeezed Gaussian states. https://doi.org/10.1088/1674-1056/ad8dc0

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