Demonstration of a 0.8 W continuous wave bulk laser around 2 μm in a Tm³⁺:Ga-rich BGG glass

Efficient lasing of Ga-rich BGG bulk glasses doped with Tm 3+ is demonstrated. Two BGG bulk samples with Tm 3+ ion concentrations of 1.27×10 20 cm −3 and 2.54×10 20 cm −3 were tested for their laser performance. In-band pumping was realized using a continuous-wave (CW) homemade Er-doped fiber laser at 1600 nm. A maximum slope efficiency of 27.7% was demonstrated with respect to the absorbed pump power. The emission cross-section was retrieved from the laser efficiency data for three different lasing wavelengths and compared with the theoretical calculations. The power scaling potential of the Tm 3+ :BGG glass was investigated and a maximum output power of 0.8 W was achieved.