Passive Phase Locking Coherent Combination of Solid-State Lasers through Stimulated Brillouin Scattering Effect

Abstract

The stimulated Brillouin scattering (SBS) effect, a new approach to the combination of solid-state lasers, can be actualized via coherent synthesis. In this paper, a solid-state laser based on SBS passive phase locking, utilizing the master oscillator power amplifier (MOPA) structure at the front end of the lasers, provides the amplification of the Stokes light subsequently generated. In order to reduce the influence of thermal effects on beam quality, beam-split amplification has been adopted with the same phase locking used by the back injection of the Stokes pulse. With the advantage of the combined scheme, the energy extraction efficiency of SBS coherent combination can be reached at 91.8% with coherent fringe visibility of 83%. Therefore, it provides a new way to improve the brightness through realizing the coherent combination of multi-channel solid-state lasers.