Temporal coupled-mode theory for thermal emission from multiple arbitrarily coupled resonators

TL;DR

This paper introduces a temporal coupled-mode theory to analyze and predict thermal emission spectra from complex systems of multiple arbitrarily coupled resonators, validated through numerical simulations.

Contribution

It provides a universal theoretical framework for understanding thermal emission from coupled resonators, which was previously lacking.

Findings

The theory accurately predicts complex emission spectra.

Coupling strength variations lead to anomalous spectral features.

Validated against detailed numerical simulations.

Abstract

Controlling the spectral response of thermal emitters has become increasingly important for a range of energy and sensing applications. Conventional approaches to achieving arbitrary spectrum selectivity in photonic systems have entailed combining multiple resonantly emissive elements together to achieve a range of spectral profiles through numerical optimization, with a universal theoretical framework lacking. Here, we develop a temporal coupled mode theory for thermal emission from multiple, arbtirarily-coupled resonators. We validate our theory against numerical simulations of complex two- and three-dimensional nanophotonic thermal emitters, highlighting the anomalous thermal emission spectra that can emerge when multiple resonators with arbitrary properties couple to each other with varying strengths.