We present an endlessly single-mode, bend-insensitive and highly birefringent photonic crystal fibre (PCF) for efficient wave transmission in the terahertz (THz) spectrum. To facilitate flat dispersion and high birefringence, a diamond-shaped porous core is introduced inside the Zeonex (background material)-based hexagonal porous cladding. Moreover, the dense geometrical arrangement of the regular hexagonal lattice in the cladding region holds maximum usable optical power inside the porous core. The major geometrical parameter of the proposed PCF such as core porosity has been optimized to improve the optical guiding parameters. The numerically investigated outcomes have shown an ultrahigh birefringence and numerical aperture of 0.0888 and 0.57, respectively. Apart from this, very low bending and material losses of \(3.01 \times 10^{ - 20}\) cm⁻¹ and 0.01451 cm⁻¹ with flattened dispersion variation of ± 0.2463 ps/THz/cm have been achieved over the broad THz band (i.e. 0.8–1.3 THz). Additionally, our proposed PCF sustains endlessly single-mode operation with a very high core power fraction of 75.28%. With all these promising results, the proposed PCF would be a potential candidate for polarization preserving as well as for efficient broadband transmission applications in the THz regime.

我们提出了一种无限的单模，弯曲不敏感和高双折射光子晶体光纤（PCF），用于在太赫兹（THz）频谱中进行有效的波传输。为了促进平坦分散和高双折射，在基于Zeonex（背景材料）的六角形多孔包层内部引入了菱形多孔核。而且，在包层区域中正六边形格子的密集几何排列在多孔芯内部保持最大的可用光焦度。拟议的PCF的主要几何参数（例如岩心孔隙率）已得到优化，以改善光学引导参数。数值研究的结果显示超高双折射和数值孔径分别为0.0888和0.57。除此之外，非常低的弯曲度和材料损耗在宽的THz频带（即0.8–1.3 THz）上，已经实现了（3.01×10 ^ {-20} \） cm ^-1和0.01451 cm ^-1的平坦色散变化为±0.2463 ps / THz / cm。此外，我们提出的PCF能够以75.28％的非常高的核心功率份额持续进行单模运行。有了所有这些令人鼓舞的结果，拟议的PCF将成为保持极化以及THz体制中有效的宽带传输应用的潜在候选者。