Bose-Einstein statistics in photoluminescence of quantum well excitons

The dynamics of resonant photoluminescence (PL) of quantum well (QW) excitons is studied within the thermodynamic description of the LA-phonon-assisted relaxation kinetics acid taking into account Bose-Einstein statistics of excitons. Nonclassical statistics strongly influences the effective radiative lifetime tau(opt) of quasi-equilibrium QW excitons. For a strongly degenerate gas of excitons, the law tau(opt) proportional to T (T is the effective temperature of excitons) changes and tau(opt) approaches 2 tau(R), where tau(R) is the intrinsic radiative lifetime of QW excitons. Furthermore, we show how the influence of nonclassical statistics on tau(opt) can be traced even at high T. Our approach describes self-consistently both the rise of FL, due to thermalization, and the decay of FL, due to the radiative recombination of thermalized QW excitons. Finally, we model numerically the PL kinetics of statistically degenerate indirect excitons in coupled GaAs/AlGaAs quantum wells. (C) 2000 Elsevier Science B.V. All rights reserved.