Raman identification of the in-plane axes of zincblende (100) surfaces: Basic principles and application to II–VI/III–V heterostructures

We use the interference of deformation-potential- and Frohlich-induced Raman scattering from LO phonons in zincblende materials to identify the in-plane axes of zincblende (100) surfaces and interfaces. This procedure, which allows e.g. to distinguish between the [011] and the [0–11] direction, is demonstrated experimentally for n- and p-type GaAs(100). The main potential of the method is its application to heterostructures. Here it allows the unambiguous assignment of polarized Raman scattering features from surfaces and interfaces to their characteristic symmetry directions. Two examples are presented: (i) localized vibrations of CdSe monolayers, embedded in BeTe stacks, and (ii) vibration modes of Te dimers on clean (2×1) reconstructed BeTe(100) surfaces.