A study of epitaxially stabilized FeSi2 by surface enhanced Raman scattering

Epitaxially stabilized films with the defect CsCl structure, that were grown by molecular beam epitaxy, have been studied by surface enhanced Raman scattering using a silver overlayer. We have observed that the defect‐induced phonon density of states features in the Raman signal shift from 256 cm−1 for a coherently strained film to 263 cm−1 for a relaxed one. The lower energy observed for the former can qualitatively be explained by the expansive trigonal distortion arising from the misfit of −0.5%.