Plastic optical fiber sensors and magnetic fluids: Plasmonic tunability and sensing properties for measurements

The optical properties of multimode plastic optical fibers (POFs) could be used for both the monitoring of magnetic field and for the tuning of plasmonic phenomenon, when a magnetic fluid was deposited on its cladding and it is connected in input to a plasmonic POF sensor. In this case, a magnetic field exerts a bending force on the POF covered with magnetic fluid, thus producing a variation of light in input to the plasmonic POF sensor and changing the plasmonic phenomenon. In particular, the focus of this work is the assessment of the tuning mechanism for the plasmonic phenomenon, which has been performed through a dedicated measurement approach. Preliminary experimental results are here presented to demonstrate how this approach can be used to change several plasmonic parameters, such as the sensitivity and the signal-to-noise ratio (SNR). This approach could be used in biosensing applications, where even smaller variation of the plasmonic response can significantly improve the detection of substances.