PLZT Electrooptic Q-Switch for Er:Cr:YSGG Laser

摘要

Q-switching of the Er:Cr:YSGG laser at 2.79 μm is realized using electrooptic modulators of PLZT X/65/35 ceramics. The high (but slow as compared with single crystals) electrooptical effect in PLZT allowed to construct Q-switches with an aperture larger than 4x4 mm~2, small lengths of 3-6 mm, with a control voltage of 1000-1500 V. Q-switching is realized using modulators in two modes - as a λ/2 switch placed into the laser cavity at the Brewster angle avoiding reflection losses and as a λ/4 switch with higher single pass losses due to Fresnel reflections. A higher laser output was obtained using λ/2 switching. The obtained pulses has a halfwidth of 150 ns, a pulse build-up time of 1.8-2.5 μs, a single pulse energy of 10-12 mJ as compared with 30 mJ output of the laser for the free-running mode.