Passively Q-switched 1.6 mu m Er:YAG laser with a gamma-Ga2O3:Co-based glass-ceramics as a saturable absorber

A resonantly pumped passively Q-switched Er:YAG laser operating at 1.617 and 1.645 mu m is reported with gamma-Ga2O3:Co2+-based glass-ceramics (GCs) as a saturable absorber. The maximum average output power achieved from this laser was 273 mW; the highest pulse energy was 5.9 mu J, corresponding to a pulse duration of 3.0 mu s at a repetition frequency of 31 kHz. To the best of our knowledge, this is the first time to use the gamma-Ga2O3:Co2+-based GC as a passive Q-switcher for Er:YAG lasers and this is also the first time to obtain 1.617 mu m and 1.645 mu m pulses with a GC-based saturable absorber.