Chin. Phys. B, 2022, Vol. 31(1): 014215    DOI: 10.1088/1674-1056/ac3988
Special Issue: SPECIAL TOPIC — Non-Hermitian physics
 SPECIAL TOPIC—Non-Hermitian physics Prev   Next

# Anti-$\mathcal{PT}$-symmetric Kerr gyroscope

Huilai Zhang(张会来), Meiyu Peng(彭美瑜), Xun-Wei Xu(徐勋卫), and Hui Jing(景辉)
Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education, Department of Physics and Synergetic Innovation Center for Quantum Effects and Applications, Hunan Normal University, Changsha 410081, China
Abstract  Non-Hermitian systems can exhibit unconventional spectral singularities called exceptional points (EPs). Various EP sensors have been fabricated in recent years, showing strong spectral responses to external signals. Here we propose how to achieve a nonlinear anti-parity-time ($\mathcal{APT}$) gyroscope by spinning an optical resonator. We show that, in the absence of any nonlinearity, the sensitivity or optical mode splitting of the linear device can be magnified up to 3 orders compared to that of the conventional device without EPs. Remarkably, the $\mathcal{APT}$ symmetry can be broken when including the Kerr nonlinearity of the materials and, as a result, the detection threshold can be significantly lowered, i.e., much weaker rotations which are well beyond the ability of a linear gyroscope can now be detected with the nonlinear device. Our work shows the powerful ability of $\mathcal{APT}$ gyroscopes in practice to achieve ultrasensitive rotation measurement.
Keywords:  anti-parity-time symmetry      optical gyroscope      exceptional point      Kerr nonlinearity
Received:  09 September 2021      Revised:  10 October 2021      Accepted manuscript online:  15 November 2021
 PACS: 42.50.-p (Quantum optics) 42.65.-k (Nonlinear optics) 42.81.Pa (Sensors, gyros) 06.30.Gv (Velocity, acceleration, and rotation)
Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 11935006, 11774086, and 12064010), Science and Technology Innovation Program of Hunan Province, China (Grant No. 2020RC4047), Natural Science Foundation of Hunan Province of China (Grant No. 2021JJ20036), and Natural Science Foundation of Jiangxi Province of China (Grant No. 20192ACB21002).
Corresponding Authors:  Hui Jing     E-mail:  jinghui73@foxmail.com

Huilai Zhang(张会来), Meiyu Peng(彭美瑜), Xun-Wei Xu(徐勋卫), and Hui Jing(景辉) Anti-$\mathcal{PT}$-symmetric Kerr gyroscope 2022 Chin. Phys. B 31 014215