Inter-valence-band electronic Raman scattering due to photoexcited holes in Ge1-xSix

The inter-valence-band electronic Raman scattering (IVRS) corresponding to the hole excitation from the heavy hole to light hole band has been studied in the bulk Ge1-x-Si-x alloys for 0<x<0.14. The measured Stokes energy shi ft depends on the energy of the incident photons, and also on the alloy com positions. This behavior is successfully explained invoking the resonant in terband hole transitions at selected locations in the Brillouin zone caused by the incident photons. The origin of the band width of the IVRS band is discussed in terms of lifetime broadening and momentum uncertainty during t he resonant scattering process.