Cladding-pumped, Yb:YAG-core, fiber-like waveguide laser: modeling and experiment.

We developed a model describing the performance of the cladding-pumped, Yb:YAG-core, fiber-like waveguide laser with a large cladding-to-core area ratio. We analyzed how pump absorption and laser output efficiencies depend on the Yb-doping level as well as the waveguide parameters, such as clad-to-core area ratio and waveguide length. We also determined the conditions that maximize both pump and laser efficiency.

Cascade generation at 1.62, 1.73 and 2.8 µm in the Er:YLF Q-switched laser.

We modeled cascade lasing at 1.6 and 1.7 µm and studied how it affects Q-switching at the 2.

Low-loss 'crystalline-core/crystalline-clad' (C4) fibers for highly power scalable high efficiency fiber lasers.

We report the latest progress in fabrication and laser performance of the fully crystalline double-clad 'Yb:YAG-core/undoped-YAG-clad' fibers grown by the hybrid crystal growth method. The single-crystalline ytterbium (Yb) doped yttrium aluminum garnet (YAG) fiber cores were grown by the laser heated pedestal growth (LHPG) method, and the single-crystalline undoped YAG claddings were grown by the liquid phase epitaxy (LPE) technique, in which the single-crystalline Yb:YAG cores were used as the growth seeds. The key parameters of the hybrid-grown 'crystalline core/crystalline clad' (C4) fibers, including material composition, crystal structure, and fiber propagation loss, were characterized.

Efficient resonantly-clad-pumped laser based on a Er:YAG-core planar waveguide.

We demonstrated continuous wave operation of an in-band pumped Er:YAG planar waveguide laser with the output of 75 W at 1645 nm and a slope efficiency of 64% with respect to the absorbed pump power at 1532 nm.

High-efficiency, 154 W CW, diode-pumped Raman fiber laser with brightness enhancement.

We demonstrate a high-power, high-efficiency Raman fiber laser pumped directly by laser diode modules at 978 nm. 154 W of CW power were obtained at a wavelength of 1023 nm with an optical to optical efficiency of 65%. A commercial graded-index (GRIN) core fiber acts as the Raman fiber in a power oscillator configuration, which includes spectral selection to prevent generation of the second Stokes.