Collective Dissipation of Oscillator Dipoles Strongly Coupled to 1-D Electromagnetic Reservoirs

TL;DR

This paper investigates the complex dissipative behavior of coupled harmonic oscillator dipoles interacting with 1-D electromagnetic reservoirs, revealing different regimes from weak to ultrastrong coupling and their effects on dynamics and steady states.

Contribution

It provides an exact numerical analysis of collective dipole dissipation across coupling regimes, highlighting the influence of reservoir choice and the emergence of light-matter decoupling at high coupling.

Findings

Non-Markovian effects at weak coupling.

Dependence of dynamics on reservoir type in ultrastrong coupling.

Decoupling of light and matter at very high coupling.

Abstract

We study the collective dissipative dynamics of dipoles modeled as harmonic oscillators coupled to 1-D electromagnetic reservoirs. The bosonic nature of the dipole oscillators as well as the reservoir modes allows an exact numerical simulation of the dynamics for arbitrary coupling strengths. At weak coupling, apart from essentially recovering the dynamics expected from a Markovian Lindblad master equation, we also obtain non-Markovian effects for spatially separated two-level emitters. In the so called ultrastrong coupling regime, we find the dynamics and steady state depends on the choice of the reservoir which is chosen as either an ideal cavity with equispaced, unbounded dispersion or a cavity array with a bounded dispersion. Moreover, at even higher coupling strengths, we find a decoupling between the light and matter degrees of freedom attributable to the increased importance of the diamagnetic term in the Hamiltonian. In this regime, we find that the dependence of the dynamics on the separation between the dipoles is not important and the dynamics is dominated by the occupation of the polariton mode of lowest energy.