High pressure dependence of the electronic properties of bound states in n-type GaAs

High pressure dependence of photoluminescence spectra in n-type doped GaAs, performed at liquid helium temperature, is shown to give some new insight into the electronic structure of bound states in this III–V compound and related alloys. In addition to some expected features, the evidence of several new pressure-induced effects leads to the discussion of some important electronic properties e.g., departure from the Γ_1c minimum proximity for donor levels occuring prior to the Γ-X cross-over, metal-to-nonmetal transition. An unexpected finding in the present study is a clear observation of nitrogen-related intense lines, suggesting a possible systematic N-doping of molecular beam epitaxy-grown GaAs:Si.