Statistics of microcavity polaritons under non-resonant excitation

TL;DR

This paper presents a quantum statistical model for microcavity polaritons under non-resonant excitation, highlighting the threshold behavior and transition from incoherent emission to lasing-like properties.

Contribution

It introduces a master equation approach accounting for polariton-reservoir interactions and threshold phenomena in microcavity polaritons.

Findings

Below threshold, emission is incoherent.

Above threshold, emission resembles laser output.

The model predicts a threshold depending on material and excitation parameters.

Abstract

A model describing amplification and quantum statistics of the exciton polaritons with k=0 in a non-resonantly excited semiconductor quantum well embedded in a microcavity is presented. Exploiting the bottleneck effect for exciton polaritons, it is assumed that the polaritons with k different from 0 act as a reservoir. The time evolution of the k=0 polaritons is described by a master equation, in which two- and one-polariton transitions between the mode with k=0 and the reservoir are accounted for. The k=0 mode exhibits a threshold depending on the material parameters and on the injected exciton density. Below threshold the quantum statistics of the emission is characteristic of an incoherent process, while above threshold it approaches that of a laser.