Design of Partial Liquid-Filled Hollow-Core Photonic Bandgap Fiber Polarizer

A novel polarizer is designed by liquid filling in partial air-holes of hollow-core photonic band gap fiber (PBGF) forming an asymmetric waveguide structure, which leads to one polarization leaking out while the orthogonal polarization remains propagating along the fiber with a relatively low loss. Applied a full-vector finite-element (FEM) method, a series of polarizer structures with different water-filled regions has been simulated for a better performance on the polarization extinction ratio and the insertion loss. Through optimization, the proposed polarizer has a high polarization extinction ratio more than 32 dB.