Scaling law for the compositional dependence of Raman frequencies in SnGe and GeSi alloys

Abstract

The compositional dependence of the Ge–Ge Raman mode in SnGe alloys has been measured in samples grown on Si substrates using a chemical vapor deposition technique. The experimental result, Δω(s)=(−68±5)s (where s is the Sn concentration), is in very good agreement with a theoretical prediction from a simple model with parameters adjusted to the compositional dependence of Raman frequencies in GeSi alloys.