Scalable higher-order exceptional surface with passive resonators

TL;DR

This paper introduces a scalable method to realize high-order exceptional surfaces in passive photonic resonators, enhancing sensitivity and robustness for perturbation sensing applications.

Contribution

It presents the first scalable protocol for constructing high-order exceptional surfaces using passive resonators, improving robustness and ease of experimental realization.

Findings

Enhanced sensitivity with higher-order exceptional surfaces.

Improved resilience against fabrication errors.

Feasibility of experimental implementation demonstrated.

Abstract

The sensitivity of perturbation sensing can be effectively enhanced with higher-order exceptional points due to the nonlinear response to frequency splitting. However, the experimental implementation is challenging since all the parameters need to be precisely prepared. The emergence of exceptional surface (ES) improves the robustness of the system to the external environment, while maintaining the same sensitivity. Here, we propose the first scalable protocol for realizing photonic high-order exceptional surface with passive resonators. By adding one or more additional passive resonators in the low-order ES photonic system, the 3- or arbitrary N-order ES is constructed and proved to be easily realized in experiment. We show that the sensitivity is enhanced and experimental demonstration is more resilent against the fabrication errors. The additional phase-modulation effect is also investigated.