A Fundamental Upper Bound for Signal to Noise Ratio of Quantum Detectors

Ryota Katsube; Masahiro Hotta; Koji Yamaguchi

doi:10.7566/jpsj.89.054005

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arXiv · 1910.05013

A Fundamental Upper Bound for Signal to Noise Ratio of Quantum Detectors

Ryota Katsube·Masahiro Hotta·Koji Yamaguchi

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Abstract

Quantum fluctuations yield inevitable noises in quantum detection. We derive an upper bound of signal to noise ratio for arbitrary quantum detection described by trace-class operators with discrete spectra. The bound is independent of observables to be detected and is computed by quantum fidelity of two initial quantum states. We provide applications of the upper bound.

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Ryota Katsube, Masahiro Hotta, Koji Yamaguchi. 2019-10-11. A Fundamental Upper Bound for Signal to Noise Ratio of Quantum Detectors. https://doi.org/10.7566/jpsj.89.054005

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