Abstract

Intense rapidly tunable picosecond laser pulses have been generated in the far-infrared from 30-250 μm, a range that is not well covered by other sources The transform-limited, diffraction-limited laser pulses have energies of up to 17 μJ, peak powers of more than 1 MW, a length of only 18 periods of the optical field, and focussed intensities of 0.1 GW/cm² Measurements of both the optical field amplitude and phase have been performed at 150 μm with a rapid-scanning cross-correlation technique probing the field-induced birefringence in a ZnTe crystal with a 10-femtosecond Ti:Sapphire laser [1] The far-infrared free-electron laser opens up the exciting possibility of performing non-linear experiments in a relatively unexplored spectral range

© 2000 IEEE