Abstract
We present a systematic study of indium surface segregation during molecular-beam epitaxy of (In,Ga)As on (h11) GaAs. Ultrathin InAs monolayer structures serve as segregation probes and are investigated by high-resolution x-ray diffraction and photoluminescence spectroscopy. An envelope-function analysis of the photoluminescence data reveals a strong enhancement of In segregation on the GaAs (111), (211), and (311) surfaces with respect to their (100) counterpart. Reflection high-energy electron-diffraction measurements confirm this observation, which is of fundamental importance for the understanding of non-(100)-oriented semiconductor heterostructures.