Linearly polarized single TM mode terahertz waveguide

Abstract

� 2016 Optical Society of America. We design a hollow-core terahertz (THz) waveguide guiding a single linearly polarized mode. This is achieved using a hybrid cladding, where we introduce a ring of subwavelength structures, including metal wires and air-holes. The wire-based cladding is extremely anisotropic, reflecting only transverse magnetic (TM) modes. The polarization of TM modes is further manipulated by replacing some wires with airholes. Numerical simulations confirm the guidance of only an x-polarized TM2mode over 0.36-0.46 THz in a wavelength-scale core (diameter of 1 mm). The propagation losses are of the order 0.25 dB/cm, with low bend losses <0.3 dB/cm at 0.4 THz for a bend radius of 5 cm.