A quantum multimode approach to unstable laser resonators

Abstract

A fully quantum-mechanical but phenomenological multimode description of unstable laser resonators, including the effects of the laser active medium, is presented using multivariate master equation techniques. The unstable resonator is shown to introduce a diffusive type coupling between the modes. The mode correlation function in k space is calculated and shown to become long ranged at the laser threshold. The two-time correlation function is also calculated and the intensity spectrum of the laser light is shown to be modified from the characteristic lorentzian of the single mode laser.