0.2-TW LASER SYSTEM AT 1 KHZ

We have developed a 1-kHz repetition-rate Ti:sapphire laser system tha t can simultaneously generate high peak and average powers of 0.2 TW a nd 4 W, respectively. The laser system generates 4-mJ energy pulses wi th a 20-fs pulse width. We eliminated thermal lensing in the system by cooling the Ti:sapphire crystal to 125 K. The output 20-fs pulses wer e fully characterized by use of the new technique of transient-grating frequency-resolved optical gating. We demonstrate experimentally that the pulse duration at the output is limited only by fifth-order dispe rsion. (C) 1997 Optical Society of America.