An ultra-sensitive quasi-periodic dipole resonance photonic crystal fiber sensor

Abstract

In this paper, a highly sensitive surface plasmon resonance (SPR) sensor based on photonic crystal fiber (PCF) is proposed and numerically simulated. By optimizing PCF air holes’ shape, size and position, the influence of the 12 holes near the core on the sensitivity was studied. From simulation results, it can be seen that the sensor can work in ultra-wideband wavelength range of near-infrared and mid-infrared region. Due to the obvious difference between x-polarization loss and y-polarization loss curves, it is possible to distinguish the types of polarized light without a polarimeter. Moreover, the resonance method is dipole resonance instead of quadrupole resonance. The wavelength sensitivities of x-polarized and y-polarized core modes are 20,076 nm/RIU and 37,692 nm/RIU, respectively. And the corresponding linear fitting degrees are respectively 0.9998 and 0.9999. Certainly, this sensor has a great potential application in the fields of biosensors, chemistry, environment, and medicine.