Circular-polarized beam splitter based on dielectrically chiral dual-core photonic crystal fiber

Abstract

A kind of circular polarization beam splitter (CPBS) based on dielectrically chiral dual-core photonic crystal fiber (DC-PCF) is proposed and investigated by a chiral plane-wave expansion method. The numerical results demonstrate the achievement of circular polarized beam splitter must introduce the circular asymmetry of structure and chirality of medium, where the former can shorten the coupling lengths for right- and left-handed beams and increase their difference, while the latter can decrease their difference. Then, according to the competing effect of the circular asymmetry of structure and chirality of medium in polarization and the difference of the paired coupling length, a CPBS based on chiral DC-PCF is designed. The simulation demonstrates that it possesses the high extinction ratios and wide bandwidth at the central wavelength of 1.55µm.