Finite-size fluctuations and photon statistics near the polariton condensation transition in a single-mode microcavity

TL;DR

This paper investigates how finite-size effects influence photon statistics near polariton condensation in a single-mode microcavity, revealing temperature-dependent quantum effects that differ from mean-field predictions.

Contribution

The study extends mean-field theory to include finite-size fluctuations and analyzes the resulting photon statistics in different temperature regimes.

Findings

Photon statistics differ from mean-field predictions in the fluctuation regime.

Quantum effects significantly alter photon behavior at low temperatures.

High-temperature behavior resembles that of a conventional laser.

Abstract

We consider polariton condensation in a generalized Dicke model, describing a single-mode cavity containing quantum dots, and extend our previous mean-field theory to allow for finite-size fluctuations. Within the fluctuation-dominated regime the correlation functions differ from their (trivial) mean-field values. We argue that the low-energy physics of the model, which determines the photon statistics in this fluctuation-dominated crossover regime, is that of the (quantum) anharmonic oscillator. The photon statistics at the crossover are different in the high- and low- temperature limits. When the temperature is high enough for quantum effects to be neglected we recover behavior similar to that of a conventional laser. At low enough temperatures, however, we find qualitatively different behavior due to quantum effects.