15 W diode-pumped Tm:YAG double-clad waveguide laser

Summary form only given. We present results for a planar direct-bonded double-clad waveguide comprised of a Tm:YAG core, undoped YAG inner-cladding, and sapphire outer-cladding layers. The YAG/sapphire numerical aperture is sufficient to capture most of the highly divergent radiation of a laser diode, thus allowing a side-pumped arrangement with two proximity-coupled /spl lambda//sub p/=785 nm, 20 W diode bars. This simple and efficient pumping scheme, combined with the thin waveguide dimension, leads to a high pumping intensity, as required for efficient operation of quasi-three-level laser systems.