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arXiv · 1810.08242

Conclusive Precision Bounds for SU(1,1) Interferometers

Chenglong You·Sushovit Adhikari·Xiaoping Ma·Masahide Sasaki·Masahiro Takeoka·Jonathan P. Dowling
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Abstract

In this paper, we revisit the quantum Fisher information (QFI) calculation in SU(1,1) interferometer considering different phase configurations. When one of the input modes is a vacuum state, we show by using phase averaging, different phase configurations give same QFI. In addition, by casting the phase estimation as a two-parameter estimation problem, we show that the calculation of the quantum Fisher information matrix (QFIM) is necessary in general. Particularly, within this setup, the phase averaging method is equivalent to a two parameter estimation problem. We also calculate the phase sensitivity for different input states using QFIM approach.

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Chenglong You, Sushovit Adhikari, Xiaoping Ma, Masahide Sasaki, Masahiro Takeoka, Jonathan P. Dowling. 2018-10-18. Conclusive Precision Bounds for SU(1,1) Interferometers. https://doi.org/10.1103/physreva.99.042122

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