Small signal gain optimization for a Q-switched Cr:LiSAF oscillator pumped by cw laser diodes

Summary form only given. In Q-switched lasers, one of the most important parameters is the small signal gain in the laser medium that determines the buildup time and the energy of the pulse. In Cr:LiSAF crystal, the small signal gain dramatically depends on the pumping configuration and on physical limits imposed by up-conversion process and by thermal quenching of fluorescence. In this work, we have developed an experimental method for the investigation of small signal gain per round-trip in situ (i.e. inside the cavity). We next defined the best pumping configuration for a 3% doped Cr:LiSAF crystal pumped by two diodes emitting 400 mW each at 670 nm.