Research on three-core photonic crystal fiber plasmonic sensor based on surface plasmon resonance with three V-groove microfluidic channel

A three-core photonic crystal fiber (PCF) sensor based on surface plasmon resonance (SPR) has been designed with silver film coated on the inner wall of a microfluidic detection channel with three V-grooves. The coupling characteristics and sensing properties of the proposed sensor are analyzed numerically using the full vector finite element method (FEM). The loss spectra and the sensing performance are found to be effectively tuned by the structure parameters of the plasmonic sensor. The simulation results show that an average wavelength sensitivity (WS) of 5413.3 nm/RIU is reached when the refractive index (RI) of the analyte lies in the range from 1.330 to 1.370, while the maximum WS achieves is 11400 nm/RIU, which occurs when the RI varies between 1.365 and 1.370, corresponding to a maximum RI resolution of 8.77 × 10–6 RIU. This is thus extremely sensitive to changes in analyte RI in the microfluidic channel.