A diode-pumped master oscillator power amplifier system based on a cryogenic Yb:YAG active-mirror laser has been developed.The performances of the laser amplifier at low temperature and room temperature have been investigated theoretically and experimentally.A maximum output energy of 3.05 J with an optical-to-optical efficiency of 14.7% has been achieved by using the master amplifier system.
Diode-end-pumped continuous-wave （CW） Tm：YAP and Tm：YLF slab lasers are demonstrated. The a- cut Tm：YAP and Tm：YLF slabs with doping concentrations of 4 at.-% and 3.5 at.-%, respectively, are pumped by fast-axis collimated laser diodes at room temperature. The maximum CW output powers of 72 and 50.2 W are obtained from Tm：YAP and Tm：YLF, respectively, while the pump power is 220 W, corresponding to the slope efflciencies of 37.9% and 26.6%, respectively.
