Mechanism and theoretical model of incoherent beam combining using stimulated Brillouin scattering in multimode fibers

Based on the coupled differential equations of Brillouin scattering on laser intensity, the mechanism of incoherent beam combining using stimulated Brillouin scattering was analyzed in multimode fibers. The result shows that the Stokes beam generated propagates in the LP01 mode, and the process of incoherent beam combing is an inverse process that the mixed beams are decomposed into the linearly polarized beam. The incoherent beam combining by stimulated Brillouin scattering was modeled, and the combined output power was calculated. The calculated output powers are consistent with Russel’s experimental results. The intensity distribution of the combined beam was also investigated. It shows that the combined intensity depends on the mode field size, the effective approach to increase the c