A Continuous-Wave Ho:YAlO3 Laser with Output 8.5W Pumped by a 1.91μm Laser at Room Temperature

A cw high efficient Ho:YAlO3 laser pumped by 1.91μm diode-pumped Tm:YLF laser at room temperature is realized. The maximum output power reaches 8.5W when the incident pump power is 15.6W. The slope efficiency is 63.7%, and the Tm:YLF to Ho:YAP optical conversion efficiency is 54.5%. The laser wavelength is 2118.3nm when the transmission of output coupler is 30%. The beam quality factor is M2~1.39 measured by the traveling knife-edge method.