Model studies of THz-range generation via down conversion of the radiation of Ti:Sapphire lasers in LBO crystals

Abstract

Results from model studies of the possibility of creating a source of high-power picosecond pulses of terahertz radiation via optical rectification and phase-matched down conversion of femtosecond pulses of Ti:Sapphire lasers in a nonlinear LBO crystal are presented. Modified Sellmeier equations are used in calculations. It is shown that the lengths of coherence for the generation of THz radiation at frequencies higher than 0.5 THz are more than 0.5 mm, allowing the technologically simple production of periodic structures. The maximum length of coherence is achieved for s–s type interactions in the XY plane. Phase-matched s–f type down conversion is possible only in the XY plane, including noncritical spectral matching conditions. Maximum efficiency can be expected for three-wave interactions with the polarization of interacting waves parallel to Z axis.