Modal Analysis of Acoustic Resonances in an Optical Fiber: All-Optical Excitation and Detection.

Opto-mechanical interactions in optical fibers based on Forward Brillouin Scattering (FBS) can lead to a new paradigm for the optical fiber sensing technology, since it allows monitor the surroundings of the fiber without requiring light interaction with the fiber outer medium. Point and distributed sensing schemes have been demonstrated based on FBS. The development of applications based on this nonlinear effect requires accurate knowledge of the properties of the acoustic modes behind FBS. In this work, different all-optical approaches for the excitation and detection of such transverse acoustic mode resonances in optical fibers will be presented and discussed.