Plasmonic Polarization Beam Splitter Based on Dual-Core Photonic Crystal Fiber

In this paper, two kinds of novel plasmonic polarization beam splitters based on dual-core photonic crystal fiber (DC-PCF) have been designed and analyzed through the full-vector finite element method. The metallic gold is used as the surface plasmon resonance (SPR) active metal. The coupling characteristics of the designed DC-PCF can be enhanced by the resonant coupling between the second-order surface plasmon polariton (SPP) mode and the core-guided modes. A gold layer in the designed DC-PCF is introduced to achieve an perfect splitting performance and an ultra-bandwidth compared to the designed DC-PCF with gold wire. Numerical results show the ultra-bandwidth of core A and B of the polarization beam splitter with gold layer can reach 210 and 220 nm, as the extinction ratio better than -20 dB, covering the E, S, C, and L optical communication bands. The extinction ratios of core A and B can reach to -84 and -46 dB at the wavelength of 1.55 mu m, respectively, and the length of splitter is 0.542 mm.