Numerical analysis of a compact all-fiber polarization beam splitter based on dual-core photonic crystal fiber with As2S3 thin layer

Modern-day optical systems are evolving towards miniaturization and integration, leading to higher performance demands for polarizing beam splitters (PBSs). A simple-structure and high-performance PBS based on dual-core photonic crystal fiber (DC-PCF) with As2S3 layer is proposed. The finite element method (FEM) and classical coupled-mode theory (CMT) are utilized to investigate the performance of this PBS. Simulation results demonstrate that the proposed PBS can achieve a minimum length of 2.65 mm, a minimum extinction ratio of -64 dB, an operating bandwidth of 420 nm, and a minimum insertion loss of 0.03 dB when the optimal parameters include cladding hole diameter of 1.0 mu m, central hole diameter of 2.0 mu m, lattice spacing of 2.0 mu m, and As2S3 ring layer thickness of 50 nm. Moreover, it also possesses a high birefringence of 3.58 x 10-3 and a negative dispersion of -30 ps/km/nm at 1.55 mu m. It is believed that the proposed PBS holds great potential to become a critical device in optical multiplexing technologies.