Dispersion flattened extremely high-birefringent kagome lattice elliptic core photonic crystal fiber in THz regime

Abstract

A highly birefringent elliptic porous-core photonic crystal fiber with kagome lattice cladding has been presented for terahertz (THz) wave transmission. The slotted airholes inside the elliptic core effectively disrupt the symmetry of the porous-core which offers extremely high modal birefringence whereas the kagome cladding structure results in significantly low effective material loss (EML). The birefringence of the proposed structure is \(9.73\times 10^{-2}\) and the EML is \(0.056\,{\hbox {cm}}^{-1}\) for y-polarized mode at an operating frequency of 1 THz. The suggested structure also provides very flat dispersion over a bandwidth of 300 GHz. It is highly expected that this elliptic core waveguide would be remarkably useful in numerous polarization maintaining THz applications.