BEAM COMBINING OF FIBER LASERS AND VERTICAL EXTERNAL CAVITY SURFACE EMITTING LASERS USING VOLUME BRAGG GRATINGS

Advances in high brightness laser sources with near diffraction limited beam quality outputs have enabled wide range of applications. However, physical constraints such as material heating and nonlinear effects limit the maximum achievable power of these laser sources. In order to obtain higher power level, beam combining techniques such as coherent beam combining and spectral beam combining are employed to enhance the power and brightness of a single output beam. In this thesis, we investigate various beam combining approaches using a holographic gratings based beam combiner, volume Bragg gratings, for combining the high brightness lasers sources. First, we theoretically study the performance of the beam combiners using the coupled wave equations. Then we conduct beam combining experimental demonstrations of high brightness fiber lasers in both active and passive coherent beam combining schemes using the proposed combiners. Lastly, we explore beam combining methods suitable for high brightness semiconductor lasers with the volume Bragg gratings beam combiners.Optical Science and EngineeringDoctoralUniversity of New Mexico. Dept. of Physics & AstronomyBalakrishnan, GaneshDiels, Jean-ClaudeFeezell, DanielNewell, Timoth