High-order exceptional points and enhanced sensing in subwavelength resonator arrays

TL;DR

This paper investigates high-order exceptional points in PT-symmetric subwavelength resonator arrays, revealing configurations that lead to these degeneracies and demonstrating their potential for enhanced sensing applications.

Contribution

The study introduces asymptotic methods to identify and compute high-order exceptional points in resonator arrays, advancing understanding of their configurations and sensing capabilities.

Findings

Identification of configurations leading to high-order exceptional points

Development of efficient asymptotic techniques for computation

Demonstration of sensitivity enhancement using high-order exceptional points

Abstract

Systems exhibiting degeneracies known as exceptional points have remarkable properties with powerful applications, particularly in sensor design. These degeneracies are formed when eigenstates coincide, and the remarkable effects are exaggerated by increasing the order of the exceptional point (that is, the number of coinciding eigenstates). In this work, we use asymptotic techniques to study PT-symmetric arrays of many subwavelength resonators and search for high-order asymptotic exceptional points. This analysis reveals the range of different configurations that can give rise to high-order exceptional points and provides efficient techniques to compute them. We also show how systems exhibiting high-order exceptional points can be used for sensitivity enhancement.