Excitation intensity and temperature dependence of photoluminescence in mid-infrared region for lattice-matched InAs/GaAsSb superlattice grown by metalorganic vapor-phase epitaxy

Abstract

Lattice-matched InAs/GaAs_0.08Sb_0.92 superlattices were grown on InAs substrates via metalorganic vapor-phase epitaxy, and the excitation intensity dependence of photoluminescence (PL) was measured from 20 to 300 K. The observed spectra were compared with the calculated spontaneous emission transitions. At 20 K, the changes in the calculated and measured spectral shapes with the carrier density in the wells closely concur. The blue shift of the emission peak, as the excitation intensity increased, was due to emission from a higher-order band. We determined the specific wavelengths at which the luminescence intensity increased rapidly at certain excitation intensities. These results broaden the spectral range. At 300 K, the PL spectrum was obtained only under strong excitation. Furthermore, higher-order transitions were also dominant in this case.