Raman scattering from interface modes inGa1−xInxSb/InAs superlattices

In this study we use Raman scattering from ${\mathrm{Ga}}_{1\mathrm{-}\mathit{x}}$ ${\mathrm{In}}_{\mathit{x}}$Sb/InAs grown by molecular-beam epitaxy superlattices to identify and study interface modes. Those modes are localized around the interfaces of the superlattices. We identify three types of longitudinal interface modes; two GaAs-like and one InSb-like. The frequency and the Raman activity of those modes are in good agreement with theoretical calculations. In addition, it is shown that the interface modes can be used to identify the interface composition (InSb or GaAs) for a variety of samples grown under controlled shutter sequences.