Modal makeup of transmission eigenchannels

TL;DR

This paper explores the relationship between transmission eigenchannels and quasi-normal modes in disordered media, revealing how their interplay explains the spectral and transmission properties of wave transport.

Contribution

It provides a novel framework expressing the transmission matrix as a sum over modes, linking eigenchannels to individual resonant modes across a broad spectral range.

Findings

Transmission eigenvalues are explained by off-resonant mode excitation.

Eigenchannel correlation frequencies relate to mode phasing.

The approach clarifies wave transport control in disordered media.

Abstract

Transmission eigenchannels and quasi-normal modes are powerful bases for describing wave transport and controlling transmission and energy storage in disordered media. Here we elucidate the connection between these approaches by expressing the transmission matrix (TM) at a particular frequency as a sum of TMs for individual modes drawn from a broad spectral range. The wide range of transmission eigenvalues and correlation frequencies of eigenchannels of transmission is explained by the increasingly off-resonant excitation of modes contributing to eigenchannels with decreasing transmission and by the phasing between these contributions.