Dual Polarized High Sensitivity Photonic Crystal Fiber Surface Plasmon Resonance Sensor Coated with Indium Tin Oxide

In this paper, we present a tetragonal cluster-based photonic crystal fiber (PCF) surface plasmon resonance (SPR) sensor with high wavelength sensitivity (WS). Indium tin oxide (ITO), as a dielectric material with adjustable photoelectric properties and low loss in the infrared range, is used in this sensor. The central rectangular air hole is used to construct an asymmetric structure which enables the sensor work in y and x polarization. We optimized the structural parameters of the sensor and the result shows that the sensor has high WS of 31,500 nm/RIU and 31,000 nm/RIU, wavelength resolution of 3.17 × 10⁻⁶ RIU and 3.23 × 10⁻⁶ RIU, maximum AS of 141.0 RIU⁻¹ and 148 RIU⁻¹, the refractive index (RI) detection range of 1.32–1.42 for y and x polarization, respectively. The sensor shows great potential in the detection of plasma, ethanol, and silicone oil.