Transverse Effects in Phase Conjugate Laser MirrorsBased on Stimulated Brillouin Scattering

The temporal and spatial reflectance of phase conjugate mirrors based on stimulatedBrillouin scattering (SBS) was investigated both theoretically and experimentally. A novelnumerical model was used that incorporates the transverse mode structure of the pump beam andthe reflected beam into the differential equations describing the scattering process. Theexperiments were performed with a Q-switched Nd:YAG laser in fundamental mode operationand SF6 at 21 bar as the SBS medium. The excellent agreement with the theoreticalresults indicates that the inclusion of the transverse intensity distribution is necessary for a realisticdescription of SBS.