The Jaynes-Cummings model breaks down when the cavity significantly reduces the emitter's free-space emission rate

TL;DR

This paper demonstrates that the Jaynes-Cummings model fails when the cavity significantly suppresses the emitter's free-space emission, and introduces a more accurate Hamiltonian for all regimes within the rotating wave approximation.

Contribution

It provides a new Hamiltonian that accurately describes strong light-matter interactions even when free-space emission is minimized, extending beyond the Jaynes-Cummings model.

Findings

Jaynes-Cummings model breaks down with reduced free-space emission

Proposes a Hamiltonian valid across all regimes within RWA

Highlights importance for quantum protocol optimization

Abstract

Strong coupling between a single resonator mode and a single quantum emitter is key to a plethora of experiments and applications in quantum science and technology and is commonly described by means of the Jaynes-Cummings model. Here, we show that the Jaynes-Cummings model only applies when the cavity does not significantly change the emitter's emission rate into free-space. Most notably, the predictions made by the Jaynes-Cummings model become increasingly wrong when approaching the ideal emitter-resonator systems with no free-space decay channels. We present a Hamiltonian that provides, within the validity range of the rotating wave approximation, a correct theoretical description that applies to all regimes. As minimizing the coupling to free-space modes is paramount for many cavity-based applications, a correct description of strong light-matter interaction is therefore crucial for developing and optimizing quantum protocols.