Effective bath model for arrays of coupled non-Hermitian nanoresonators

TL;DR

This paper introduces a simple effective bath model for arrays of coupled non-Hermitian nanoresonators, enabling accurate predictions of their optical properties and facilitating the design of complex nanophotonic systems.

Contribution

The authors develop and validate a novel effective bath model based on a continuum of modes to describe coupled non-Hermitian nanoresonator arrays, extending predictive capabilities beyond traditional numerical methods.

Findings

The model accurately predicts dispersive and reactive modes in coupled resonator systems.

Effective coupling constants depend non-trivially on inter-resonator distance.

The approach is applicable to larger systems difficult to solve with finite-element methods.

Abstract

Nanophotonics systems have recently been studied under the perspective of non-Hermitian physics. Given their potential for wavefront control, nonlinear optics and quantum optics, it is crucial to develop predictive tools to assist their design. We present here a simple model relying on the coupling to an effective bath consisting of a continuum of modes to describe systems of coupled resonators, and test it on dielectric nanocylinder chains accessible to experiments. The effective coupling constants, which depend non-trivially on the distance between resonators, are extracted from numerical simulations in the case of just two coupled elements. The model predicts successfully the dispersive and reactive nature of modes for configurations with multiple resonators, as validated by numerical solutions. It can be applied to larger systems, which are hardly solvable with finite-element approaches.