Experimental Study on High-Sensitivity MoS2Thickness Modulation Refractive Index Sensor Based on SPR-PCF

In chemical and biological analysis, different substances have different requirements for RI detection. In this article, we propose and experimentally validate a molybdenum disulfide (MoS2)-modulated surface plasmon resonance (SPR) sensor. Due to the high effective refractive index (RI) of MoS2, the detection accuracy of the sensor after MoS2 modulation is good. The numerical simulation results verify that the MoS2 film has a good improvement effect on the performance of fiber sensing. The sensor is fabricated by coating a silver film and a MoS2 film on a photonic crystal fiber (PCF) using a magnetron sputtering method. First, the optimal sensing length and sputtering time of the silver film are determined experimentally, and the MoS2 film is coated on the optimal silver-based sensor. Experimental results show that the maximum sensitivity of the MoS2-modulated sensor in the detection range of RI from 1.415 to 1.420 is 16000 nm/RIU. The RI sensitivity of the MoS2-modulated sensor is increased by 167.35% compared with that of silver-based sensors, which means that the sensor is suitable for high-sensitivity detection applications of specific substances.