Two parallel polarized terahertz waves generation from quasi-phase-matching stimulated polariton scattering with periodically-inverted GaAs

Abstract

In this work, we theoretically analyze the generation of two parallel polarized terahertz (THz) waves from coupled optical parametric oscillations (OPOs) with periodically-inverted GaAs by stimulated polariton scattering (SPS). We analyze collinear phase-matching (CPM) conditions for bulk GaAs generating a THz wave and quasi-phase-matching (QPM) conditions for periodically-inverted GaAs generating two THz waves. The analysis results indicate that the frequencies of the two THz waves and the frequency differences between the two THz waves are efficiently tuning by varying grating periods of periodically-inverted GaAs. The photon flux densities (PFD) of the two THz waves are calculated. The generating PFD of the two THz waves are efficiently enhanced by injecting a Stokes seed laser or increasing pump intensity. The scheme proposed in this work enable new applications of THz wave in imaging and spectroscopy.