Abstract In this letter, a hollow core ring based circular photonic crystal fiber (PCF) is explored and proposed with stably supporting terahertz (THz) orbital angular momentum (OAM) states transmission. The proposed PCF is discussed, investigated, analyzed and simulated with optical properties in a terahertz frequency spectrum ranging from 0.20 THz to 0.55 THz. The OAM and THz communication-based parameters of the fiber are deliberated extensively under various conditions through using the full vector finite element method (FEM). Some significant parameters of PCF like effective refractive index difference, dispersion profile, confinement loss, effective mode area, numerical aperture, power fraction and isolation effects are numerically discussed for the first time with their effects and applications on the THz OAM transmission. The mentioned PCF has supported 48 OAM modes with a large effective refractive index difference up to 1 0 − 3 . The confinement loss of the PCF around 1 0 − 10 dB/cm, and the average dispersion profile variation is 1.0055 ps/THz/cm. Besides, the highest numerical aperture and power fraction of the PCF are 0.35 and 99.7882%, respectively. Also, a higher isolation power effect around 267 dB, and crosstalk less than −14 dB are obtained for the PCF. Moreover, this kind of PCF would be a robust candidate for efficient THz OAM transmission, high capacity and high feasibility of optical fiber communications.

中文翻译：

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设计用于光通信中引导太赫兹轨道角动量光束的光子晶体光纤

摘要 在这封信中，探索并提出了一种基于空心环的圆形光子晶体光纤 (PCF)，其稳定支持太赫兹 (THz) 轨道角动量 (OAM) 态传输。在 0.20 THz 到 0.55 THz 的太赫兹频谱中讨论、研究、分析和模拟了所提出的 PCF 的光学特性。通过使用全矢量有限元方法 (FEM)，在各种条件下广泛讨论了光纤的基于 OAM 和 THz 通信的参数。首次数值讨论了 PCF 的一些重要参数，如有效折射率差、色散分布、限制损耗、有效模式面积、数值孔径、功率分数和隔离效应，以及它们对太赫兹 OAM 传输的影响和应用。提到的 PCF 支持 48 种 OAM 模式，具有高达 1 0 - 3 的大有效折射率差。PCF 的限制损耗约为 1 0 − 10 dB/cm，平均色散分布变化为 1.0055 ps/THz/cm。此外，PCF 的最高数值孔径和功率分数分别为 0.35% 和 99.7882%。此外，PCF 获得了大约 267 dB 的更高隔离功率效应和小于 -14 dB 的串扰。此外，这种 PCF 将成为高效 THz OAM 传输、高容量和光纤通信高可行性的有力候选者。PCF 的最高数值孔径和功率分数分别为 0.35% 和 99.7882%。此外，PCF 获得了大约 267 dB 的更高隔离功率效应和小于 -14 dB 的串扰。此外，这种 PCF 将成为高效 THz OAM 传输、高容量和光纤通信高可行性的有力候选者。PCF 的最高数值孔径和功率分数分别为 0.35% 和 99.7882%。此外，PCF 获得了大约 267 dB 的更高隔离功率效应和小于 -14 dB 的串扰。此外，这种 PCF 将成为高效 THz OAM 传输、高容量和光纤通信高可行性的有力候选者。