28W average power hydrocarbon-free rubidium diode pumped alkali laser.

We present experimental results for a high-power diode pumped hydrocarbon-free rubidium laser with a scalable architecture. The laser consists of a liquid cooled, copper waveguide which serves to both guide the pump light and to provide a thermally conductive surface near the gain volume to remove heat. A laser diode stack, with a linewidth narrowed to approximately 0.

Room-temperature laser action at 4.34.4 mum in CaGa(2)S(4):Dy(3+).

We report room-temperature mid-IR laser operation in a new low-phonon-frequency nonhygroscopic host crystal, calcium thiogallate (CaGa(2)S(4)) . Laser action at 4.314.

Three-level Q-switched laser operation of ytterbium-doped Sr(5)(PO(4))(3)F at 985 nm.

Ytterbium-doped Sr(5)(PO(4))(3)F was successfully lased at 985 nm in quasi-cw mode with a slope efficiency of 74% and an absorbed threshold energy of 18 mJ. Q-switched slope efficiencies of 21% were obtained with a maximum energy of 9.4 mJ in 8.

Continuous-wave and passively Q-switched cladding-pumped planar waveguide lasers.

Greater than 12 W of average output power has been generated from a diode-pumped Yb:YAG cladding-pumped planar waveguide laser. The laser radiation developed is linearly polarized and diffraction limited in the guiding dimension. A slope efficiency of 0.

Multimode-diode-pumped gas (alkali-vapor) laser.

We report what we believe to be the first demonstration of a multimode-diode-pumped gas laser: Rb vapor operating on the 795 nm D1 resonance transition. Peak output of approximately 1 W was obtained using a volume-Bragg-grating stabilized pump diode array. The laser's output radiance exceeded the pump radiance by a factor greater than 2000.

Laser activity at 1.18, 1.07, and 0.97 microm in the low-phonon-energy hosts KPb2Br5 and RbPb2Br5 doped with Nd3+.

For the first time to the authors' knowledge, laser activity has been achieved in low-phonon-energy, moisture-resistant bromide host crystals, neodymium-doped potassium lead bromide (Nd3+:KPb2Br5) and rubidium lead bromide (Nd3+:RbPb2Br5; RPB). Laser activity at 1.07 microm was observed for both crystalline materials.

Resonance transition 795-nm rubidium laser.

Population inversion of the 2P 1/2 and 2S 1/2 levels and continuous-wave, three-level laser oscillation at 795 nm on the D1 transition of the rubidium atom has been demonstrated. Using a titanium sapphire laser as a pump source, we obtained a slope power efficiency of 54% relative to absorbed pump power, consistent with homogeneous broadening of the rubidium pump and laser transitions. The end-pumped rubidium laser performance was well described by use of literature spectroscopic and kinetic data in a model that takes into account ground-level depletion and a pump spectral bandwidth that is substantially larger than the collisionally broadened pump transition spectral width.

1-W average power levels and tunability from a diode-pumped 2.94-microm Er:YAG oscillator.

A tunable Er:YAG laser, side pumped by a quasi-cw InGaAs diode array, generates > 500 mW of power at 2.936 microm. The cavity is a 4-cm plano-concave resonator that uses total internal reflection on the pump face of the Er:YAG crystal to couple the diode emission into the resonating modes of the oscillator.

Properties of Cr:LiSrAIF(6) crystals for laser operation.

We have performed several physical and optical measurements on the Cr:LiSAF (LiSrAlF(6)) laser material that are relevant to its laser performance, including thermal and mechanical properties, water durabilities, and Auger upconversion constants. The expansion coefficient, Young's modulus, fracture toughness, thermal conductivity, and heat capacity are all used to determine an overall thermomechanical figure of merit for the crystal. An investigation of the water durability suggests that the cooling solution should be maintained at pH = 7 to ameliorate problems associated with water dissolution.

Q-switched laser at 912 nm using ground-state-depleted neodymium in yttrium orthosilicate.

A ground-state-depleted laser is demonstrated in the form of a Q-switched oscillator operating at 912 nm. By using Nd(3+) as the active ion and Y(2)SiO(5) as the host material, the laser transition is from the lowest-lying Stark level of the Nd(3+4)F(?) level to a Stark level 355 cm(-1) above the lowest-lying one in the (4)I(9/2) manifold. The necessity of depleting the ground (4)I(9/2) manifold is evident for this level scheme as transparency requires a 10% inversion.

Stimulated-emission cross sections of the (5)F(1)-(5)I(5) and (5)F(1)-(5)I(6) transitions of Pm(3+) in a phosphate glass.

We report a laser cavity measurement of stimulated-emission cross sections for both the (5)F(1)-(5)I(5) (0.93-microm) and (5)F(1)-(5)I(6) (1.1-microm) laser transitions of Pm(3+) ions in a lead-indium-phosphate glass host.