Nonlinear frequency shift of acoustic waves in semiconductor plasmas

Abstract

The evolution of nonlinear instability of an electron acoustic wave from the coupling of pair modes of slightly different frequencies in semiconductor plasmas is studied. The linear dispersive properties of pair modes, viz., pump wave and sideband wave, are analyzed on employing the quantum hydrodynamic model. The linear fields of pair modes couple through a second order convective term to unfold the nonlinear beat frequency of the electron acoustic mode. The nonlinear dispersion relation leads to the derivation of the growth rate of three-wave parametric instability. The quantum effects of semiconductor electrons are taken through the exchange-correlation potential, the Bohm potential, and statistical Fermi pressure. The growth rate is also analyzed graphically. This study seeks its applications in semiconductor devices.