Review of Brillouin Active Fiber Based Acoustooptic Sensors

摘要

Brillouin active fibers, based on stimulated Brillouin scattering (sBs), have been extensively studied as ambient sensors by exploiting quartz fiber intrinsic acoustooptic properties. Thus, the fiber is inherently a sensor, as opposed to fiber Bragg gratings, in which lines have to be photolithographically etched on the fiber by UV light. The sBs threshold enables sensing to be switched on and off in standard communication fibers, leading to fiber dual use. They have also been examined as combined optical and acoustic waveguides for joint optical and acoustic sensing. Success of these sensors lies in lowering the sBs threshold to achieve low power, short fiber length and multi-Stokes line generation. Numerous schemes have been proposed and tested, such as fiber rings, and they will be surveyed. The inherent optical feedback by the back-scattered Stokes wave leads to instabilities in the form of optical chaos. This paradigm of optical chaos serves as a test for fundamental study of chaos and its suppression and exploitation in practical application in communication and sensing.