Quasi-Distributed Refractive Index Sensing by Stimulated Brillouin Scattering in Tapered Optical Fibers
Aldo Minardo, Luigi Zeni, Romeo Bernini, Ester Catalano, Raffaele Vallifuoco
Abstract
In this paper, we demonstrate that multiple tapers in optical fibers allow for quasi-distributed refractive index sensing via a high spatial resolution Brillouin Optical Frequency-Domain Analysis (BOFDA) configuration. We first characterize, theoretically and experimentally, the variation of the Brillouin frequency shift (BFS) with the diameter of the tapered fiber. Then, we characterize the dependence of the BFS from the outer refractive index in an optical fiber taper with a waist diameter of 10 µm. Finally, we show that more tapers can be realized along the same fiber, in order to provide multi-point refractive index sensing.
Topics & Concepts
Brillouin scatteringOpticsRefractive indexMaterials scienceOptical fiberNormalized frequency (unit)Brillouin zoneGraded-index fiberStep-index profileRefractive index profileFiber optic sensorOptoelectronicsPhysicsPhase-locked loopPhase noiseFrequency synthesizerAdvanced Fiber Optic SensorsPhotonic and Optical DevicesAdvanced Fiber Laser Technologies