Low-Loss Single Mode Terahertz Microstructure Fiber with Near-Zero-Flattened Dispersion

An octagonal cladding based microstructure optical fiber (MOF) with rotated circular manner core is proposed to obtain low loss, and near zero flat dispersion characteristics. The guiding properties of the designed MOF are numerically investigated by utilizing electromagnetic full vectorial finite element method (FV-FEM) with absorbing boundary condition (ABC). The simulation outcomes reveal the ultra-low effective absorption loss of 0.047 cm^–1 and high core power fraction of 54% at the operating frequency of 1 THz. Besides, the proposed MOF exhibits near zero and flat dispersion about from 0.91 to 1.09 THz frequency bands. It is demonstrated that at the optimized design parameter, dispersion variation of less than 0.2 ps/THz/cm can be obtained. Furthermore, the designed MOF shows single-mode propagation over a wide range of operating frequency. The proposed MOF can be fabricated using sol–gel technique and would be a potential candidate in numerous THz applications.