Gain mechanisms and lasing in II-VI compounds

In this paper. we present a microscopic theory for the physical mechanisms giving rise to lasing in II-VI semiconductor media. Both photons and carriers are consistently treated within the same fully quantum mechanical footing by means of nonequilibrium Keldysh Green's function techniques. The highly excited medium is described in terms of a strongly Coulomb correlated electron-hole plasma. Numerical results are presented for the emission, absorption and gain characteristics of ZnCdSe-ZnSSe MQWs in good agreement with recent experimental results.