Exceptional surface-enhanced Rotation Sensing with Robustness in an optical microcavity

TL;DR

This paper introduces an exceptional surface in non-Hermitian optical microcavities that combines robustness against perturbations with highly sensitive rotation detection, significantly improving gyroscope performance.

Contribution

It proposes a novel EP surface structure that maintains robustness while enabling three orders of magnitude sensitivity enhancement in rotation sensing.

Findings

EP surface offers robustness against fabrication errors.

Rotation causes system to move away from EPs, boosting sensitivity.

Sensitivity is improved by three orders of magnitude over traditional methods.

Abstract

Exceptional points (EPs) are special singularities of non-Hermitian Hamiltonians. At an EP, two or more eigenvalues and the corresponding eigenstates coalesce. Recently, EP-based optical gyroscope near an EP was extensively investigated to improve the response to rotation. However, the highly resultant dimensionality in the eigenstate space causing from the EP-based system is sensitivity to more external perturbations, that is, the great response at EPs requires strict implementation conditions. To solve this problem, a new non-Hermitian structure was proposed that realizes an exceptional surface (EP surface) constructed of numerous EPs embedded in a high-dimensional parameter space. With respect to the isolated EPs, non-Hermitian EP surface provides additional degrees of freedom to permit the undesired perturbations (such as fabrication errors) shifts along the EP surface which corresponds to the robustness. On the other hand, the rotation will force the system away from these EPs obtaining a sensitivity enhancement of three orders of magnitude, compared to the traditional Sagnac effect rotation detecting. The EP surface system has a potential to combine robustness with enhanced sensitivity of the rotation.