Ultra-short polarization splitter based on a plasmonic dual-core photonic crystal fiber with an ultra-broad bandwidth

A compact polarization beam splitter based on a gold-filled photonic crystal fiber with a square lattice is proposed. The full vector finite element method is used to design and characterize the proposed ultra-compact and ultra-broadband polarization splitter. The plasmonic plays an important role in order to achieve an ultra-short length of 56.33 µm with a high extinction ratio of 132.92 dB at the wavelength of 1.55 µm. It can ensure an ultra-broad bandwidth of 530 nm, from 1225 to 1755 nm, covering all the communication bands with an extinction ratio better than 20 dB. The proposed polarization splitter may be a promising candidate in communication due to its ultra-short length and ultra-broad bandwidth.