Temperature dependence of the photoluminescence from InP/GaAs type-II ultrathin quantum wells

摘要

Temperature dependence of the photoluminescence (PL) spectra has been investigated for InP/GaAs type-II ultrathin quantum wells (QWs). Room temperature PL has been observed for 1.43 monolayer thick ultrathin QW. Fitting parameters of the Bose-Einstein empirical relation for ultrathin QWs show that the temperature dependence of PL peak energy is similar to the temperature dependence of the band gap for InP and GaAs materials. In addition, we have also determined the PL quenching mechanism from the Arrhenius-like plot of integrated PL intensity. Thermal escape of carriers from these ultrathin QWs into the GaAs barrier is mainly responsible for the PL quenching with temperature. This is also supported by the observation that the PL intensity related to the GaAs barrier increases with increasing temperature.