Refractive index sensor based on selectively liquid infiltrated dual core photonic crystal fibers

In this paper, a novel refractive index sensor based on liquid infiltrated dual-core photonic crystal fibers (PCFs) is proposed. The two fiber cores, separated by an air hole inside the cross-section of the designed PCFs, are filled with analyte liquids which form two independent waveguides. A novel and simple refractive index sensing system is proposed using mode coupling theory and its sensing performances have been studied numerically. The results show that the refractive index sensor with 1 cm length PCF has a large sensing range and high sensitivity of −65,166.10 nm/RIU at wavelength 1.25 μm.