Frequency Mixing of Acoustic Waves in Semiconductors

Abstract

In this paper the phenomenon of frequency mixing of acoustic waves in semi-conductors as a result of electron-phonon interaction through a strain dependent dielectric constant (SDDC) has been analytically investigated. The dependence of subharmonic generation on account of electron-phonon interaction due to SDDC on the various parameters i.e. ω, β, γ, etc., displays marked differences with that due to piezoelectric interaction, studied earlier by Conwell, Ganguly and Spectror. Numerical results have been presented for the typical case of a BaTiO₃ sample. It is found that for such materials (with large dielectric constants) the electron-phonon interaction effects due to SDDC are much more important than piezoelectric interaction in determining the sub-harmonic genera- tion.