Holmium-doped Lu2O3, Y2O3, and Sc2O3 for lasers above 2.1μm

Efficient room-temperature laser operation was obtained in the wavelength range from 2117 nm to 2134 nm with Ho:Lu2O3 and Ho:Y2O3 as the active materials. With an FBG-stabilized Tm-doped fiber laser as the pump source, the maximum slope efficiency and output power of the Ho:Y2O3 laser were 63% and 18.8W, respectively. With Ho:Lu2O3 the respective values were 76% and 25.2W. With Ho:Sc2O3 as the active material the accessible wavelength range could be expanded to 2158 nm in a diode-pumped setup. (C) 2013 Optical Society of America