Numerical Modeling of Cryogenic Temperature Sensors Based on Plasmonic Oscillations in Metallic Nanoparticles Embedded Into Photonic Crystal Fibers

We perform a numerical investigation on the operation of an inline temperature sensor based on the inclusion of metallic nanoparticles into photonic crystal fibers (PCFs). This creates a simple, yet robust, platform which can be used to investigate the properties of nanoparticles, for sensing, spectroscopy, and optical switching applications. The optical response of gold nanoparticles embedded in the PCF matrix was evaluated as a function of temperature and the use of the structure as an inline fiber-optic temperature sensor is theoretically described. A blue-shift in the localized surface plasmon resonance related peak, as well as narrowing of the plasmon resonance, was observed upon decreasing the temperature of the nanoparticle embedded into the PCF at very low temperatures, thus permitting the operation of this sensing platform at cryogenic temperatures