Suppression of stimulated Brillouin scattering in optical fibers using fiber Bragg gratings

We propose a novel scheme for suppressing stimulated Brillouin scattering in optical fibers. The scheme makes use of a single or a sampled Bragg grating fabricated within the fiber used for transmitting intense Q-switched pulses. The grating is designed such that the spectrum of the Stokes pulse generated through stimulated Brillouin scattering falls entirely within its stop band. We show numerically that 15- ns pulses with 2- kW peak power can be transmitted though a 1- m- long fiber with little energy loss using this scheme. A sampled grating can be used for longer fibers but its coupling coefficient should be higher. The proposed scheme should prove useful for double- clad fiber lasers and amplifiers. (C) 2003 Optical Society of America.