LAUSR

Abstract A surface plasmon resonance (SPR) refractive index (RI) sensor based on a D-shaped Hi-Bi photonic crystal fiber (PCF) is investigated with finite element method. Through changing the asymmetry of the fiber core along x- and y- axis, it is found that the Hi-Bi structure can greatly enhance the plasmon resonance at near-infrared wavelength, thus effectively reducing the FWHM. Benefiting from this, the designed sensor can provide higher FOM than other works previously reported. In addition, from the design and optimization of sensor structure and material, it is found that compared with the refractive index of the material, the structure has little influence on the sensitivity of the sensor, but can effectively improve the resonance intensity of SPR, which has certain guiding significance for the design and optimization of such PCF SPR sensors in the future.