Anti-resonant hollow-core terahertz fiber based on Bragg structure elements

• Published in: Optical fiber technology Vol. 80; p. 103448
• Main Authors: Ding, Jin-Long, Chen, Ming-Yang, Ding, Li-Sha, Dong, Zhe-Yan
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.10.2023
• Subjects: Absorption loss; Anti-resonant fiber; Bragg structure; Confinement loss; Terahertz fiber; Absorption loss; Anti-resonant fiber; Confinement loss; Terahertz fiber; Bragg structure
• ISSN: 1068-5200; 1095-9912
• DOI: 10.1016/j.yofte.2023.103448

•Hollow-core fiber based on Bragg structure can effectively enhance its confinement capacity.•The total transmission loss can still be reduced by an order of magnitude by the introduction of additional dielectric layers.•The bending loss caused by mode coupling can be suppressed by the introduced antiresonant unit. An anti-resonant hollow-core terahertz fiber applying Bragg structure as the basic unit is presented, the basic unit is composed of two or three concentric tubes which is cut and connected by an outer ring. Simulations results show that the proposed fiber has the transmission characteristics of both conventional anti-resonant structure and Bragg fiber, and its confinement loss could be 2–3 orders of magnitude lower than that of an anti-resonant hollow-core terahertz fiber composed of only a single semi-tube as the anti-resonant unit, and the total transmission loss is one order of magnitude lower, which can achieve a low transmission loss of 0.5 dB/m or less with the bandwidth of 0.15 THz. In addition, the appropriated choice of the outer ring diameter can effectively suppress the mode coupling between the core and cladding, thereby reducing its confinement loss and bending loss. The proposed fibers show great potential for applications in terahertz wave communication and the fabrication of terahertz sensors.