DISORDERED GARNETS CA3(NB, GA)5O12-ND3+ - PROSPECTIVE CRYSTALS FOR POWERFUL ULTRASHORT-PULSE GENERATION

Disordered garnets Ca3(Nb, Ca)5O12:Nd3+ grown by the Czochralski method are used in a pulsed picosecond laser to generate 5-10-ps pulses in passive mode-locking trains of 120-180 ns and 1.6 mJ of energy at 1.06-mu-m. The evolution of the pulse parameters along the train is investigated. Direct time-resolved measurements allow us to determine the positive linear chirp of the laser frequency, which causes the pulse spectral broadening of DELTA-v = 50-60 cm-1. The chirped pulses are compressed in the external grating compressor. The measured pulse duration of 2 ps is limited by the time resolution of the streak camera.