Growth, thermal properties and laser performance of Er,Pr:Y 2.8 Sc 1 Al 4.2 O 12 : a promising multi-wavelength laser crystal

Er,Pr:Y 2.8 Sc 1 Al 4.2 O 12 (Er,Pr:YSAG) crystal has been successfully grown by the Czochralski method. The FWHM of XRC is 0.050°, indicating the high crystalline quality. Besides, thermal conductivity of the crystal is 5.76 W/mK, which is higher than lots of other heavily Er 3+ doped crystals meaning the great potential in solid-laser gain media application. Luminescence characters of the crystal at 3 μm are investigated in detail to determine the laser generation potential. An intensive reduce is occurring on the fluorescence lifetimes of 4 I 13/2 energy level (0.75 ms) of Er 3+ ions after Pr 3+ ions co-doped, giving the enormous promotion on the multi-wavelength laser generation at 3 μm. Besides, the as-grown Er,Pr:YSAG crystal realizes the dual-wavelength laser generation at 2694 and 2825 nm for the first time, and an average laser power of 235 mW is realized. The M 2 factor is used to quantify the laser output beam quality, which value are 1.65/1.56 along x and y axis, meaning a high-brightness laser generation of Er,Pr:YSAG crystal at 3 μm.