TRANSVERSE BRILLOUIN EFFECT CHARACTERIZATION IN OPTICAL FIBERS AND ITS GEOMETRICAL ASPECTS

Measurements of the transverse Brillouin-induced acoustic response, wi th durations up to 150 ns, are reported for different optical fibers, using a cross-phase modulation experimental setup. The observed discre pancies with the published theoretical model are discussed. We point o ut that fibers' asymmetry turns out to contribute significantly to the amplitude of the acoustic response. An accurate damping parameter for acoustic; waves is measured, and the quantification of the existing m ixed torsional-radial modes is also reported for the first time to our knowledge.