| Popis: |
The spectroscopy properties and wavelength tunability of diode pumped laser based on Tm3+, Ho3+ co-doped (Gd3-xGax)(Ga5-y Al y)O12 mixed gadolinium-gallium-aluminium garnet (Tm, Ho:GGAG) single crystal were investigated. A fiber (core diameter 400 μ m, NA = 0.22) coupled laser diode was used for longitudinal pumping of Tm, Ho:GGAG crystals. The laser diode was operating in the pulsed regime (5 ms pulse length, 10 Hz repetition rate, 785 nm emission wavelength, maximum power amplitude 16.8 W). The 150 mm long hemi- spherical laser resonator consisted of a flat pumping mirror (HR @ 1.852.11 μm, HT @ 0.78 μm) and concave (r = 150 mm) output coupler with a reflectivity of ≈97% @1.8 2.10 m. Wavelength tuning was accomplished by using 1.5 mm thick SiO2 birefringent plate. For the sample with 3.97 at.% Tm, 0.38 at.% Ho concentration, the measured maximal output power amplitude was 1.04 W at 2086 nm with a slope efficiency of 23.6 % and the tunability range 19862110 nm (124 nm). For the sample with 7.65 at.% Tm, 0.68 at .% Ho concentrations, the measured maximal output power amplitude was 2.30 W at 2090 nm with a slope efficiency of 26.5 % and the tunability range 20032116 nm (113 nm). |
