2.79 μm YSGG:Cr:Er laser pumped at 790 nm

2.79 μm quasi-CW laser operation at room temperature was achieved from a YSGG:Cr:Er crystal. The output from the crystal, which was longitudinally pumped with a Ti:sapphire laser at 790 nm, was self-terminating. Under quasi-CW pumping, the length of the emitted pulses decreased exponentially with increasing pump power. The self-terminating behavior is explained by thermal effects with a computer simulation of the population mechanisms in the crystal. This simulation considers not only the common cross-relaxation and up-conversion processes, but also the inverse processes. They turn out to be of the same importance as the normal processes. The YSGG:Cr:Er crystal depends so critically on the laser parameters that it is an ideal candidate for testing the system of rate equations