Cryogenic Yb:YAG Laser Pumped by VBG-Stabilized Narrowband Laser Diode at 969 nm

We present the laser performance of Yb:YAG at different cryogenic temperatures pumped by a volume Bragg grating (VBG)-stabilized narrowband fiber-coupled diode laser emitting at 968.7 nm for the first time to the best of our knowledge. A maximum output power of 6.54 W with a slope efficiency as high as 64.6% is achieved at 140 K. The optimum temperature for 968.7 nm and 0.35 nm bandwidth VBG-stabilized pump source is found to be 140 K for Yb:YAG.