Gain saturation in Nd:doped laser materials

Abstract

Saturation of gain in Nd:doped silicate, phosphate, and fluorophosphate glasses, and in doped crystals of YAG and YLF was observed during amplification of 1064 and 1053 nm pulses with durations of 1.0, 9.0, and 50 ns. Saturation fluences were computed from measured external parameters by means of the Frantz-Nodvik model for a homogeneous amplifier. The resulting values of saturation fluence increase with increasing output fluence and were only slightly greater at 50 ns than at 1 ns, suggesting that the lower level lifetime is less than 1 ns.