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arXiv · 1510.05249

Metrology with $\mathcal{PT}$-symmetric cavities: Enhanced sensitivity near the $\mathcal{PT}$-phase transition

Zhong-Peng Liu·Jing Zhang·Şahin Kaya Özdemir·Bo Peng·Hui Jing·Xin-You Lü·Chun-Wen Li·Lan Yang·Franco Nori·Yu-xi Liu
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Abstract

We propose and analyze a new approach based on parity-time ($\mathcal{PT}$) symmetric microcavities with balanced gain and loss to enhance the performance of cavity-assisted metrology. We identify the conditions under which $\mathcal{PT}$-symmetric microcavities allow to improve sensitivity beyond what is achievable in loss-only systems. We discuss its application to the detection of mechanical motion, and show that the sensitivity is significantly enhanced in the vicinity of the transition point from unbroken- to broken-$\mathcal{PT}$ regimes. We believe that our results open a new direction for $\mathcal{PT}$-symmetric physical systems and it may find use in ultra-high precision metrology and sensing.

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Zhong-Peng Liu, Jing Zhang, Şahin Kaya Özdemir, Bo Peng, Hui Jing, Xin-You Lü, Chun-Wen Li, Lan Yang, Franco Nori, Yu-xi Liu. 2015-10-18. Metrology with $\mathcal{PT}$-symmetric cavities: Enhanced sensitivity near the $\mathcal{PT}$-phase transition. https://doi.org/10.1103/physrevlett.117.110802

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