Formation process of high-field domain in superlattices observed by photoluminescence spectra branch

We report photoluminescence Stark-shift behaviors under various optical exc itation intensity for a GaAs/AlAs superlattice. The study clarifies the for mation process of the high-field domain by analyzing photoluminescence (PL) spectra. We observed changes in splitting feature of the PL spectra, by va rying excitation carrier density near resonance voltages between the Gamma states. This clarifies how the inner electric field in superlattices varies by increasing carrier density.