Highly scattering fibers used as sensors
Résumé
(< 1500 characters) : The use of nanoparticles is gaining large interest in modern photonic technology, mainly because nanoparticles can drastically change the properties of optical media. Here, a custom special optical fiber has been considered for investigation. The fiber presents a MgO-based nanoparticles core, and standard telecommunication size. Modified Chemical Vapor Deposition technique, together with the spontaneous phase separation, permit to grow inside the core a random distributed pattern of nanoparticles. The nanoparticle increases the scattering, which is, in general, an unwanted occurrence. Nevertheless, interesting applications can emerge in sensor field. Interestingly, the fabrication method of these sensors is simplified, since it does not require the inscription of reflective elements such as Bragg gratings. In this work we focus on the distributed sensing applications offered by the enhanced backscattering. The fiber has been characterized by the use of an Optical Backscatter Reflectometer. The backscattered intensity, induced by the nanoparticles, is tens of dB larger than the one shown by standard telecom single mode fiber. During this presentation, we will discuss about the ability of such fibers to be used as refractive index sensors and on a setup for multiplexed distributed optical fiber sensors capable of resolving temperature distribution with a spatial resolution of 2.5 mm over multiple fibers interrogated simultaneously.