Raman scattering from acoustic phonons confined in Si nanocrystals

Abstract

We have observed Raman scattering from acoustic phonons confined in Si nanocrystals. It was found that the Raman spectra depend strongly on the size of the nanocrystals and the peaks shift to higher frequencies as the size decreases. We also found that the depolarized Raman spectra appear at much lower frequencies than the polarized ones.