Nonlinear distortion and spatial dispersion of intense terahertz generation in lithium niobate via the tilted pulse front technique

Abstract

We systematically investigate the influences of the input infrared spectrum, chirp, and polarization on the emitted intense terahertz spectrum and spatial dispersion in lithium niobate via optical rectification. The terahertz yield and emission spectrum depend on both the chirp and spectrum of the input pump laser pulses. We also observe slight non-uniform spatial dispersion using a knife-edge measurement, which agrees well with the original predictions. The possible mechanism is the nonlinear distortion effect caused by high-energy laser pumping. Our study is very important and useful for developing intense terahertz systems with applications in extreme terahertz sciences and nonlinear phenomena.