A Simple and Efficient Plasmonic Sensor in Light Diffusive Polymer Fibers

A low-cost plasmonic sensor based on a polymeric light diffusive optical fiber (LDF) has been designed, realized, and experimentally tested. The developed surface plasmon resonance (SPR) sensor has been realized by sputtering a gold nanofilm on the LDF. The work also presents a simple modal filter, realized by covering the LDF with an aqueous solution. Notably, this modal filter improves the signal-to-noise ratio (SNR) of the SPR sensor thanks to the filtering of the higher modes, without losing its sensitivity.