A Tunable Single- and Triple-Wavelength Nd:GGG Laser in the 1.3 μm Range with 880 nm LD Direct Pumping

We report a single- and triple-wavelength Nd:GGG laser operating in the 1.3 μm wavelength range with 880 nm laser diode pumping directly into the 4F3/2 emitting level. For a pump power of 24.85 W, a single wavelength of 1331 nm is obtained with an output power of 2.95 W and a slope efficiency of 15.9%. By inserting a 0.1 mm thick BK7 glass etalon and adjusting its tilting angle, we achieve tunable lasing wavelengths of 1323, 1331, 1336, 1338, and 1346 nm with maximum output powers of 1.94, 2.46, 1.92, 1.80, and 1.17 W, as well as slope efficiencies of 8.07%, 10.25%, 7.98%, 7.48%, and 4.85%, respectively. We realize simultaneous triple-wavelength laser at 1323, 1331, and 1336 nm, for the first time, up to our knowledge, with a maximum output power of 1.66 W and a slope efficiency of 6.6%.