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arXiv · 2503.14306

Revisit on quantum parameter estimation approach for Mach-Zehnder interferometry

Bing-Shu Hu·Xiao-Ming Lu
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Abstract

The Mach-Zehnder interferometer is a fundamental tool for measuring phase shifts between two light paths, serving as a crucial prototype for achieving high-precision measurements in various scientific and technological applications. In this study, we analyze different models for estimating relative phase shift in a general two-arm Mach-Zehnder interferometer. We demonstrated that single-parameter estimation models can be reduced from the two-parameter estimation model by imposing appropriate constraints on the parameter space. To make quantum Fisher information of the single-parameter estimation models meaningful, the corresponding constraints must be guaranteed in the experiment implementation. Furthermore, we apply the quantum Fisher information approach to analyze the Mach-Zehnder interferometer with the an input state composed of a displaced squeezed vacuum state and a coherent state, providing insights into the precision limits of such configurations.

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Bing-Shu Hu, Xiao-Ming Lu. 2025-03-18. Revisit on quantum parameter estimation approach for Mach-Zehnder interferometry. https://doi.org/10.1088/1572-9494%2Fadcf08

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