A New Technique to Electro-Optically Q-switch Uniaxial Gain Materials.
Presented by Mr. Loyiso MAWEZA on 10 Jul 2014 from 10:20 to 10:40
Type: Oral Presentation
Track: Track C - Photonics
We introduce a new technique of Electro-Optic Q-switching which exploits the polarization dependence of a uniaxial gain medium. Conventional Electro-Optic Q-switched cavities require both a polarizer and a wave plate in addition to an Electro-Optic Modulator (EOM) which rotates the beam polarization within a few nano-seconds. The new technique eliminates the need for a polarizer, which is an advantage for short pulse, high peak power Q switched lasers. This is because polarizers are susceptible to damage and can significantly lengthen the cavity, which increases the output pulse length. Uniaxial gain materials like Nd:YVO4 have different thermo-dioptric constants in two crystallographic directions, which causes the two polarization states to experience different thermal lens strengths for a-cut crystals. The cavity can be switched between stable and unstable states by rotating the polarization with a Pockels cell. The results in a rapid change in the cavity quality, which Q-switches the resonator. The presentation will first review conventional Electro-Optic Q-switched methods after which the new technique will be introduced. It will then be shown how the new technique was implemented in a short Nd:YVO4 cavity. The experiments confirmed that the new technique is viable and operating regimes, advantages and disadvantages of the new technique will be presented.
Dr. Hencharl Strauss and email@example.com