A Stable 2012.1 nm Single-Longitudinal-Mode Tm:YAG Ceramic Laser with Volume Bragg Grating and Fabry–Perot Etalon

We demonstrate a stable single longitudinal mode Tm:YAG ceramic laser operating at a single wavelength of 2012.1 nm. The single-longitudinal-mode Tm:YAG ceramic laser is obtained by employing volume Bragg grating as one cavity mirror and inserting a Fabry–Perot etalon into the laser cavity. A maximum single longitudinal mode output power of 165 mW with a slope efficiency of 6.6% is achieved under the pump power of 5.02 W. The laser has a beam quality of M²=1.18 at the maximum single longitudinal mode output power.