PULSE AMPLIFICATION OF A SINGLE-FREQUENCY CR-FORSTERITE LASER

Stable single-longitudinal-mode operation of a tunable gain-switched C r:forsterite oscillator-amplifier system is reported. A novel coupled- cavity oscillator configuration provides a low-threshold fluence of 0. 3 J cm(-2), making the system attractive for laser media with low gain or high parasitic loss. Nearly transform-limited pulses with instrume nt-limited bandwidths of 150 MHz have been obtained across a 100-nm wa velength range, limited by the cavity optics. A range of forsterite cr ystals with Cr4+ concentration in the 3-21 x 10(18)-cm(-3) range has b een used for investigation of amplifier performance in single- and dou ble-pass configurations. (C) 1998 Optical Society of America.