Dual hollow-core anti-resonant fiber polarization beam splitter with ultra-short length and ultra-wide bandwidth

Abstract

Apolarization beam splitter based on a dual hollow-core anti-resonant fiber is proposed. In the horizontal direction, elliptical shapes are introduced to form two hollow cores, with an air gap between the ellipses serving as a mode-coupling channel. Using the finite element method, a specific analysis is conducted on the influence of various structural parameters of the dual hollow-core anti-resonant fiber on the coupling length of the x-polarized and y-polarized modes, as well as the extinction ratio of higher-order modes.Optimizing the structural parameters of the fiber has led to the design of a dual hollow-core anti-resonant fiber polarization beam splitter that is exceptionally compact, measuring just 1.306 cm in length. This device achieves a broad bandwidth of 420 nm ranging from 1.53 µm to 1.95 µm and maintains superior single-mode characteristics within this wavelength spectrum. The novel dual hollow-core anti-resonant fiber is poised to play a significant role in the optical communication systems and optical network technologies.