Low-loss terahertz polarization splitter based on an asymmetric dual-suspended-core fiber

A relatively simple design of a terahertz (THz) polarization splitter based on an asymmetric dual-suspended-core fiber is proposed. One core is formed by two intersecting rectangular dielectric strips with dissimilar thickness, whereas the other is a round solid core suspended by crossed dielectric strips with the same thickness. The distance between the cores can be adjusted to ensure a short splitting length and low transmission loss. A THz polarization splitter with a length of 1.27 cm is realized with a low transmission loss of 0.53 and 0.67 dB for the x- and y-polarization modes, respectively. An extinction ratio of about −20  dB and a broad bandwidth of 0.046 THz are demonstrated.