CW DIODE PUMPING AND FM MODE-LOCKING OF A ND-KGW LASER

We have demonstrated cw diode end pumping of Nd:KGW, a novel solid-sta te gain medium, with rip to 30% conversion efficiency into near-TEM(00 ) (M(2) < 1.05) output at lambda = 1.067 mu m for a pump level of 2.7 W. The slope efficiency was limited by intracavity reflections to 36%; however, direct comparison to a similar Nd:YAG laser indicates the sa me intrinsic slope efficiency of approximate to 60%. FM mode locking o f this laser at 200 MHz: has produced 12 ps pulses (compared to 16 ps for Nd:YAG), although an intracavity etalon was required. Considerable reduction in pulse width is possible (the line width limit is approxi mate to 0.5 ps) but different techniques may be necessary. Spatial hol e burning was evident in both the approximate to 120 GHz free-running spectrum and the etalon-limited mode-locked spectrum.