Simulation of surface plasmon resonance temperature sensor based on liquid mixture-filling microstructured optical fiber

Abstract

We demonstrate a temperature sensor based on surface plasmon resonances supported by a six-hole microstructured optical fiber (MOF). The air holes of the MOF are coated with a silver layer and filled with a large thermo-optic coefficient liquid mixture (ethanol and chloroform). The use of all six fiber holes and their relatively large size should facilitate the coating of the silver and the filling of the liquid mixture. Temperature variations will induce changes of coupling efficiencies between the core-guided mode and the plasmonic mode, thus leading to different loss spectra that will be recorded. The refractive index of the liquid mixture is close to that of the MOF material, which will enhance the coupling efficiency and the sensitivity. Our numerical results indicate that temperature sensitivity as high as 5.6 nm/K can be achieved and that the most sensitive range of the sensor can be tuned by changing the volume ratios of ethanol and chloroform.