Photoluminescence from the 2D electron-gas and many-body effects as a probe of the crystalline quality of pseudomorphic GaAs/InGaAs/AlGaAs and GaAs/n(GaAs)10(n+1)(InAs)m/AlGaAs MODFETs

We have performed low temperature (5K) photoluminescence (PL) measurements in order to study the crystalline quality of pseudomorphic modulation-doped field effect transistors (MODFET's) grown by MBE. MODFET's based on GaAs/AlGaAs with either an InGaAs or a (GaAs)n(InAs)m short period superlattice (SPS) channel have been studied. On modulation doped structures, the presence of free carriers into the channel strongly affects the PL emission,. In this paper, we present a study of PL line shape of MODFET structures with different channel thicknesses and growth conditions. A correlation between the PL line shape and these parameters is clearly observed.