INFLUENCE OF ELECTRON TEMPERATURE ON POPULATION INVERSION AMONG ELECTRONIC SUBBANDS IN OPTICALLY PUMPED SEMICONDUCTOR QUANTUM WELLS

Abstract

A detailed theoretical study on population inversion among different electronic subbands, induced by hot-electron interactions with LO-phonons and with photons, is presented for an optically pumped AlGaAs-GaAs double quantum well system which may behave as a 3-level far-infrared laser generator. The influence of electron temperature and pumping intensity on the population inversion in this laser system proposed very recently, has been studied through calculating the inter-subband electronic scattering rate caused by electron-LO-phonon interactions and by optical absorption scattering. Theoretical results obtained from this study indicate that at a fixed pumping intensity, the population inversion among different electronic subbands can be tuned by varying electron temperature through, e.g. applying an in-plane electric field.