Methods of generating superbroadband terahertz pulses with femtosecond lasers

This paper presents experimental results and an analysis of methods of generating terahertz (THz) radiation, using femtosecond laser sources: generation by photoconductive semiconductor antennas, nonlinear-optical generation of the difference frequency or optical rectification, and generation using optical breakdown in gases under the action of femtosecond pulses. An undoped semiconductor crystal of indium arsenide (InAs) located in a magnetic field, an electrooptic ZnTe crystal, an organic DAST crystal, and an optical spark in air were used as generators of THz radiation