Experimental Results

Experimental characterization and applications of forward Brillouin scattering in various types of optical fibers are presented. Measurements are compared with the predictions of analysis and calculations whenever possible. Results include the forward Brillouin scattering spectra of bare and coated single-mode fibers, multi-core fibers, and polarization-maintaining fibers. Both intra-modal and inter-modal process in polarization-maintaining fibers are reported. The contributions of radial and torsional-radial modes are identified and classified. The interplay of forward Brillouin scattering and the Kerr effect is characterized as well. Position-integrated, point-measurement, and spatially distributed analyses of liquid media outside the fiber are demonstrated. The sensing of surrounding media is enabled by forward Brillouin scattering processes, even though guided light does not come in contact with such media. The results establish a new class of optical fiber sensors which are based on forward Brillouin scattering. Additional application demonstrations include monitoring the elastic properties of coating layers, electro-opto-mechanical oscillators, and forward Brillouin fiber lasers. The reported results support the analysis and calculations of the preceding chapters.