Refractive index sensor of photonic crystal fiber coated with double functional layers

The invention relates to the field of photonic crystal fibers, in particular to a refractive index sensor of a photonic crystal fiber coated with double functional layers. The refractive index sensor of the photonic crystal fiber coated with the bifunctional layer comprises the photonic crystal fiber, the photonic crystal fiber comprises a fiber core and periodic air holes formed in the periphery of the fiber core, and the photonic crystal fiber is a triangular lattice photonic crystal fiber or a D-shaped photonic crystal fiber. The gold and the CsPbBr3 quantum dots are used as dual-function layers and sequentially cover the side wall of at least one central air hole surrounding the fiber core of the photonic crystal fiber, or the gold and the CsPbBr3 quantum dots sequentially cover the axial side parabolic surface of the photonic crystal fiber. The CsPbBr3 quantum dot/gold double-layer coated photonic crystal fiber refractive index sensor designed by the invention can better measure the refractive index of a