Lasing and squeezing of composite bosons in a semiconductor microcavity - art. no. 063809

We consider a. semiconductor microcavity etched into a small post structure in which the polariton modes become quantized. When moderate amounts of ex citons are injected, large gain for the lowest confined polariton results f rom exciton-exciton scattering. We show that gain is sufficient to compensa te for typical losses of GaAs structures, and stimulated emission of the co nfined polariton is eventually achieved at an exciton density below that wh ere Rabi splitting collapses. We study the dependence of the threshold exci ton density on post size, polariton loss rate and lattice temperature. We s tudy the polariton statistics, and show that far above threshold, typical t ransition from super-Poissonian to Poissonian statistics is preserved. Exci ton-exciton interaction produces a self-phase modulation, resulting in enha nced frequency noise, and into a net increase of the emission linewidth far above threshold. We show how to produce a number-squeezed state using corr elation between frequency and number noise. A numerical example of a realis tic structure is also analyzed in detail.