A Non-Hermitian Sensing via Matching Singularities Using Multi-port Excitation

This paper proposes an interesting method to improve the sensitivity of refractive index sensing. It solves the problem of fabrication errors in non-Hermitian sensors, which lead to deviations from the ideal state. we show a sensing system based on a printed circuit board. It is very simple, low in cost, easy to integrate, and applicable. It paves the way for the practical application of non-Hermitian sensors.