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arXiv · 2407.14739

Nonreciprocal Quantum Sensing

Dong Xie·Chunling Xu
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Abstract

Nonreciprocity can not only generate quantum resources, but also shield noise and reverse interference from driving signals. We investigate the advantages of nonreciprocal coupling in sensing a driving signal. In general, we find that the nonreciprocal coupling performs better than the corresponding reciprocal coupling. And we show that homodyne measurement is the optimal measurement. A single non-reciprocal coupling can increase measurement precision up to 2 times. Using $N$ non-reciprocal couplings in parallel, the measurement precision can be improved by $N^2$ times compared with the corresponding reciprocal coupling. In a non-zero temperature dissipative environment, we demonstrate that the nonreciprocal quantum sensing has better robustness to thermal noise than the reciprocal quantum sensing.

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Dong Xie, Chunling Xu. 2024-07-20. Nonreciprocal Quantum Sensing. https://doi.org/10.1103/physrevapplied.22.064072

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