Nonequilibrium Model of Photon Condensation

TL;DR

This paper presents a nonequilibrium model for photon condensation in dye-filled microcavities, analyzing the conditions under which photons thermalize or behave like a laser, based on absorption, emission, temperature, and cavity losses.

Contribution

It introduces a detailed nonequilibrium model of photon condensation, highlighting the transition between thermal equilibrium Bose-Einstein distribution and laser-like behavior.

Findings

Photon thermalization depends on absorption and emission rates.

Low temperatures or high cavity losses prevent thermalization.

Photon behavior transitions from Bose-Einstein condensation to lasing.

Abstract

We develop a nonequilibrium model of condensation and lasing of photons in a dye filled microcavity. We examine in detail the nature of the thermalization process induced by absorption and emission of photons by the dye molecules, and investigate when the photons are able to reach a thermal equilibrium Bose-Einstein distribution. At low temperatures, or large cavity losses, the absorption and emission rates are too small to allow the photons to reach thermal equilibrium and the behavior becomes more like that of a conventional laser.