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.

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.

Wavelength tuning in cryogenically cooled lasers based on Er-doped orthovanadates.

Continuous tuning between 1590 and 1612 nm has been demonstrated in cryogenically cooled lasers with composite active media consisting of Er:YVO, Er:LuVO, and Er:GdVO crystals resonantly pumped by a fiber-coupled laser diode emitting at 1529 nm. Wavelength tuning was implemented using an intracavity single-plate birefringent filter.

Thermal characterization, crystal field analysis and in-band pumped laser performance of Er doped NaY(WO(4))(2) disordered laser crystals.

Undoped and Er-doped NaY(WO4)2 disordered single crystals have been grown by the Czochralski technique. The specific heat and thermal conductivity (κ) of these crystals have been characterized from T = 4 K to 700 K and 360 K, respectively. It is shown that κ exhibits anisotropy characteristic of single crystals as well as a κ(T) behavior observed in glasses, with a saturation mean free phonon path of 3.

Resonantly cladding-pumped Yb-free Er-doped LMA fiber laser with record high power and efficiency.

We report the results of our power scaling experiments with resonantly cladding-pumped Er-doped eye-safe large mode area (LMA) fiber laser. While using commercial off-the-shelf LMA fiber we achieved over 88 W of continuous-wave (CW) single transverse mode power at ~1590 nm while pumping at 1532.5 nm.