In this paper explore the terahertz (THz) wave generation based on cavity phase matching (CPM) difference frequency generation (DFG) in a GaAs crystal sheet. This scheme applying cavity phase matching (CPM) is proposed. The wave propagation of the higher frequency pump wave is parallel to the wave propagation of the lower frequency pump wave, and both of them are perpendicular to the cavity length in a GaAs crystal sheet. The THz wave is emitted the nonlinear crystal. We calculated the optimized cavity length in a GaAs crystal sheet at the range of 100-1000μm (0.3-3THz). Our estimates illustrate that THz wave output corresponds to the power conversion efficiency of 50 times in CPM-DFG for in DFG. The result is shown that this scheme is efficient to obtain THz wave.

Abstract. We study on the generation of efficient terahertz (THz) wave. This scheme applying cavity phase matching (CPM) optical parametric oscillator (OPO) with a GaAs crystal sheet by CO 2 laser is proposed. The THz wave is emitted the nonlinear crystal. We calculated the optimized cavity length in a GaAs crystal sheet at the range of 100-1000 μm. The result is shown that CPM-OPO scheme is efficient to obtain efficient THz wave.