Observation of inhomogeneous spectral broadening of stimulated brillouin scattering in an optical fiber

We report experimental results which show that the stimulated Brillouin scattering (SBS) spectrum in an optical fiber is inhomogeneous, exhibiting spectral broadening and hole burning under cw monochromatic laser excitation. This phenomenon arises from the waveguide interaction of the pump and Stokes signals and is a fundamental property of SBS in waveguiding systems due to their ability to confine a fan of radiation wave vector directions.