BEHAVIOR OF IN0.48GA0.52P/(AL0.2GA0.8)0.52IN0.48P QUANTUM-WELL LUMINESCENCE AS A FUNCTION OF TEMPERATURE

The photoluminescence (PL) of an ${\mathrm{In}}_{0.48}$${\mathrm{Ga}}_{0.52}$P/(${\mathrm{Al}}_{0.2}$${\mathrm{Ga}}_{0.8}$${)}_{0.52}$${\mathrm{In}}_{0.48}$P multiple-quantum-well sample composed of wells of various widths has been measured as a function of temperature. The presence of LO-phonon replicas at low temperature for the largest well indicates that the PL is dominated by localized excitons. This is further confirmed by the variation of the PL peak energies and PL linewidths as the temperature is increased above 4.2 K. The temperature dependence of the integrated PL intensities shows that the major loss mechanism is thermal activation of electron-hole pairs out of the wells followed by nonradiative recombination in the barriers. The experimental data substantiate the proposition that the poor thermal characteristics of visible lasers is caused by carrier leakage out of relatively shallow wells.