Parametric dispersion and amplification in semiconductor plasmas: Effects of carrier heating

Abstract

Using the hydrodynamic model of a semiconductor plasma, the influence of carrier heating on the parametric dispersion and amplification has been analytically investigated in a doped III–V semiconductor, viz. n-InSb. The origin of the phenomena lies in the effective second-order optical susceptibility ( χ e (2)) arising due to the induced nonlinear current density of the medium. Using the coupled-mode theory, the threshold value of pump electric field (| E 0T| para) and parametric gain coefficient ( α para) are obtained via χ e (2). The relevant experiment has not been performed. Proper selection of the doping level not only lowers | E 0T| para required for the onset of parametric excitation but also enhances α para. The carrier heating induced by the intense pump modifies the electron collision frequency and hence the nonlinearity of the medium, which in turn further lowers | E 0T| para and enhances α para by a factor of ∼10 3 and ∼2×10 2, respectively. The results strongly suggest that the incorporation of carrier heating by the pump in the analysis leads to a better understanding of parametric processes in solids and gaseous plasmas, which can be of great use in the generation of squeezed states.