High-Power, Compact, and Stable Side-Pumped Tm:YAG Laser with 119 W Output

A high-power, compact and stable rod-shaped Tm:YAG solid-state laser pumped by a side-coupled laser diode (LD) has been reported. A laser module composed of three LDs with a wavelength of 780 nm was used to pump the Tm:YAG bonded at both ends laterally, achieving high-power laser output. To reduce the device volume, a symmetrical straight short cavity was built, and a single-channel water cooling method was used. The highest continuous laser output of 119 W at 2.02 μm was obtained at a cooling temperature of 12℃, with a photon-to-photon conversion efficiency of 18% and a slope efficiency of up to 32.7%. The system can maintain stable maximum power output within 2 hours with power fluctuations less than 1%. The beam quality factors in the x and y directions were measured to be 21.01 and 21.68, respectively.