Four-photon polarization spectroscopy of induced plasma oscillations in a skin layer of semiconductors

Abstract

Probe-beam scattering spectra have been obtained for four-wave mixing of laser waves in the skin layer of intrinsic semiconductors. The spectra were recorded using the frequency dispersion of orthogonally polarized radiation, which arises as a result of nonlinear optical interaction with conduction-band electrons. The mixing of two counterpropagating light waves in a semiconductor, implemented under nonlinear excitation of longitudinal density oscillations in the plasma electron subsystem of the semiconductor, is theoretically considered. This mixing is shown to lead to the rotation of the probe-beam polarization vector. The results obtained are of interest, e.g., for studying optical metamaterials based on thin-film structures.