Optimization of the Tilted-Pulse-Front Terahertz Excitation Setup Containing Telescope

Optimization of the telescopic tilted-pulse-front terahertz excitation setup with respect to the imaging errors is given. A guideline is presented in the form of simple analytical formulae describing the optimal geometrical configuration of the telescopic setup. Pump pulse distortions and terahertz wave-front distortions are analyzed by ray tracing calculations supposing near-infrared pump pulses with 200 fs transform limited pulse length. The detrimental effects of imaging errors in a tilted-pulse-front terahertz source can be significantly reduced by using telescopic imaging instead of one-lens. It is also shown, that in the case of the one-lens setup significant, and in the case of the telescopic setup, less significant reduction of the imaging errors can be achieved by using achromat lens(es) instead of singlet one(s). Calculation results show that the telescopic setup consisting of two achromat lenses is the most promising choice among the practically relevant schemes.