Broad bandwidth and 600 μm length photonic crystal fiber polarization filter at the communication window of 1.55 μm

Abstract

A broad bandwidth and 600-μm length photonic crystal fiber polarization filter at the communication window of 1.55 μm is proposed. The physical parameters are analyzed by the finite element method. In the structure, the loss is 705.81 dB/cm for y-polarized mode and 24.06 dB/cm for x-polarized mode at the wavelength of 1.55 μm; the y-polarized mode will be filtered out because of this property. The bandwidth of an extinction ratio (ER) better than −20 dB is 65 nm when the filter length is 600 μm, and the ER is −41 dB at the communication wavelength of 1.55 μm. The filter structure is simple and easy to produce, and it can be used to produce a single-polarization filter.