Chinese Control Conference (CCC)

Exponentially Enhanced Sensitivity Revival via Fine Loss and Gain Tuning

Liying Bao

Published Jul 28, 2025• 0 citations

Abstract

It has been shown that exponentially enhanced sensitivity can be obtained by utilizing quantum non-Hermitian properties, such as the skin effect. However, in previous works only the accompanied quantum noise in the input waveguide was considered, while the complex ambient gain and loss noises were not taken into account. In this work, we study the sensitivity of non-Hermitian quantum sensors under complex ambient noises. We find that the gain and loss structures play a crucial role in the sense that by finely adjusting the gain and loss, quantum sensors can recover its original exponential sensitivity. Our results provide an effective means to improve the performance of quantum sensors in real physical environments.

DOI: 10.23919/ccc64809.2025.11179146

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