Simple but accurate estimation of light-matter coupling strength and optical loss for a molecular emitter coupled with photonic modes

TL;DR

This paper introduces a straightforward, parameter-free method based on macroscopic quantum electrodynamics to accurately estimate light-matter coupling strength and optical loss in molecular emitters coupled with photonic modes, relevant for cavity QED applications.

Contribution

It develops a simple, accurate estimation technique combining mQED and pseudomode approach, and proves the equivalence of wavefunction and Lindblad dynamics under certain conditions.

Findings

Method accurately estimates coupling strength and optical loss.

Analytical and numerical validation of the approach.

Equivalence between wavefunction and Lindblad dynamics under Lorentzian Purcell factors.

Abstract

Light-matter coupling strength and optical loss are two key physical quantities in cavity quantum electrodynamics (cQED), and their interplay determines whether light-matter hybrid states can be formed or not in chemical systems. In this study, by using macroscopic quantum electrodynamics (mQED) combined with a pseudomode approach, we present a simple but accurate method which allows us to quickly estimate the light-matter coupling strength and optical loss without free parameters. Moreover, for a molecular emitter coupled with photonic modes (including cavity modes and plasmon polartion modes), we analytically and numerically prove that the dynamics derived from the mQED-based wavefunction approach is mathematically equivalent to the dynamics governed by the cQED-based Lindblad master equation when the Purcell factor behaves like Lorentzians.