Acoustoelectric absorption in semiconductors with dominant acoustic-phonon scattering

Abstract

It has been shown that the well-known Cohen-Harrison-Harrison (CHH) model of the collision term for electrons in a semiconductor with an acoustic wave is invalid for energy-dependent relaxation times. A modified collision term has been used to calculate the absorption coefficient of an acoustic wave. Our calculations show that for the case of acoustic-phonon scattering and an intermediate range of frequencies, i.e., ν_s/ν₀<ql<ν₀ν_s is ν₀ is average thermal velocity and ν_s is the sound velocity), the values of the absorption coefficients are appreciably different from those obtained using the CHH model; in the two extreme limits, i.e., ql<ν_s/ν₀ and ql>ν₀/ν_s, we obtain some results similar to those using CHH model.