We report the laser performance of a low-propagation-loss neodymium-doped Gd<sub>3</sub>Ga<sub>5</sub>O<sub>12</sub> (Nd:GGG) waveguide fabricated by pulsed-laser deposition. An 8- ?m -thick crystalline Nd:GGG film grown upon an undoped Y<sub>3</sub>Al<sub>5</sub>O<sub>12</sub> substrate lases at 1.060 and 1.062 µm when pumped by a Ti:sapphire laser operating at 740 or 808nm.Using a 2.2% output coupler, we observed a 1060-nm laser threshold of 4mW and a slope efficiency of 20%. Laser action was also achieved, for what we believe is the first time in Nd:GGG, on the quasi-three-level 937-nm transition. With a 2% output coupler at this wavelength a laser threshold of 17mW and a 20% slope efficiency were obtained. This demonstration of low propagation loss combined with the fact that these waveguides have a very high numerical aperture (0.75) makes pulsed-laser-deposited thin films attractive for high-power diode-pumped devices.
© 1997 Optical Society of AmericaPDF Article