Design of high-energy THz sources based on optical rectification

Different materials suitable for optical rectification are compared in terms of maximal THz generation efficiency and the spectral content. Semiconductors can be advantageous for generating higher-frequency THz pulses; however, the relative spectral width is typically smaller than that in LiNbO₃. Furthermore, it is shown that imaging errors in the tilted-pulse-front pumping scheme can lead to a THz beam with strong divergence and asymmetric intensity profile, thereby limiting applications. Optimized setup parameters were found to reduce such distortions.