An ultrabraoadband polarization splitter based on square-lattice dual-core photonic crystal fiber with a gold wire

An ultrabroadband polarization splitter based on square-lattice dual-core photonic crystal fiber with a gold wire is studied by the finite element method. Integrating a gold wire between two cores has effectively enhanced the bandwidth of the splitter. Numerical results demonstrate that the polarization splitter has an extinction ratio better than −20 dB with a broad bandwidth of 430 nm, covering almost all the O, E, S, C, L and U communication bands; Moreover, the extinction ratio at 1.55 μm can reach −78.2 dB.