Characterization Of Main Electron-Scattering Mechanisms In Ingaas/Inalas Single Quantum-Wells By Optical Modulation Spectroscopy

In this paper we report experimental results on InGaAs/InAlAs single quantum wells (SQW) obtained by photoreflectance (PR) between 5 K and 450 K. In the first part of the paper we focus on the evolution of the broadening parameter of E1H1 in the lattice matched 5 nm well width sample, E1H1 and E 2 H 2 in the lattice matched 25 nm SQW. From this study we derive information about the relative influence of interface roughness, alloy scattering, and electron phonon interactions. In the second part we apply the PR technique to the study of quantum wells near the surface in which we observe an increase of the broadening parameter. These studies show the great interest of PR technique for the qualification of materials and for the surface probe.