Tunable narrowband surface-emitted THz-radiation generated in periodically poled lithium niobate

Summary form only given. The generation of short pulse THz-radiation with ultrashort laser pulses is a well established technique. These THz-sources are based on transient photoconductivity or optical rectification in short nonlinear crystals. Recently, Lee et al. (2000) have reported narrowband THz-generation via optical rectification in periodically poled lithium niobate crystals (PPLN). The crystal length used in their experiments was limited by the strong absorption of the PPLN crystal in this wavelength range. We report for the first time on the generation of narrowband tunable THz-radiation via optical rectification in PPLN which is emitted perpendicular to the surface of the PPLN crystal.