Theoretical Investigation of Dual-wavelength Terahertz Wave Generation Based on Slant-Stripe-Type Periodic Poled Lithium Niobate Crystal

We propose a method for generating dual-wavelength terahertz radiation with a surface emitted configuration based on slant-stripe-type periodic poled lithium niobate (PPLN) crystal. The crystal is designed to be phase reserved for two difference frequency generation processes so that the predesigned dual-wavelength terahertz radiation at 1.43 THz and 2.07 THz can be achieved simultaneously. The estimated effective nonlinear coefficient as a function of the terahertz radiation frequencies is also included in our discussion. Theoretical analysis shows that the central frequency of the predesigned terahertz radiation will shift inconspicuously due to the permitted fabrication inaccuracy of the crystal period.