Plasmonic photonic crystal fiber polarization filter with asymmetry around Au-coated and liquid-filled air holes

Abstract

A novel polarization filter based on plasmonic photonic crystal fiber with Au-coated and liquid-filled air holes is presented in this paper. The coupling theory is introduced to explain the complete coupling and incomplete coupling. We can adjust the resonance point to the communication band by optimizing the parameters of the fiber structure. Numerical simulation results demonstrate that the resonance strength can reach 489.78 dB cm $$^{-1}$$ at the communication wavelength of 1.55 um in x-polarized direction. By filling liquid analyte the confinement loss can reach 572.55 dB cm $$^{-1}$$ at the wavelength of 1.55 um. When the fiber length of L equals to 800 um, the peak value of the crosstalk can reach 394.75 dB at the wavelength of 1.55 um, and the bandwidth of the crosstalk better than 20 dB is up to 180 nm when the length of the fiber L is 200 um. These features make it a promising candidate for designing new types of polarization filter devices.