Stimulated Brillouin scattering phase conjugating long multimode optical fibers properties

This paper describes and characterizes a detailed experiment that proves the phase conjugating properties of stimulated Brillouin scattering in multimode fibers (km of length), a problem still in debate in the literature, by studying the random aberrations correction abilities of this nonlinear interaction. Detailed qualitative and quantitative evaluation of aberration correction, by using the M-2 beam propagation ratio as a criterion to assess beam quality of the beams, proves the phase conjugation via SBS in long MM fibers. A new parameter to characterize the efficiency of the SBS phase conjugation process is proposed and conditions to obtain a complete healing of distortions (complete phase conjugation) are discussed. (c) 2006 Elsevier B.V. All rights reserved.