Investigation on low-loss hollow-core anti-resonant terahertz fiber

Abstract

In this work, a hollow-core anti-resonant terahertz (THz) fiber with elliptical cladding and nested tubes is proposed and fabricated. It is an effective way to reduce the loss of THz waves by transmitting them in an air core and breaking the material absorption. After parameter optimization of the initial structure, multiple transmission windows exist in the 0.2–0.8 THz band, where confinement loss is as low as 3.47×10−3cm−1 at 0.8 THz. At 0.2–0.7 THz, confinement losses lie between 10−3 and 10−2cm−1. The 3D printed samples are characterized by a THz time-domain spectroscopy system. Experimental results showed that the designed fiber structure transmits loss coefficients up to 10−2cm−1 in the 0.2–0.8 THz band (the minimum value is located at 0.46 THz, corresponding to a loss coefficient of 0.0284cm−1). The experiments show that the designed THz fiber achieves a good transmission effect.

Anti-Resonant Hollow-Core Fibers with High Birefringence and Low Loss for Terahertz Propagation

“…However, the transmission of terahertz waves is susceptible to environmental influences due to their high absorption by water vapor and certain materials, leading to significant transmission losses that hinder their development. To address this challenge, researchers have developed various low-loss waveguides for the terahertz waveband, including metal wires [11], parallel plates [12], subwavelength fibers [13], dielectric slab waveguides [14], porous-core fibers [15], and hollow-core fibers [16]. Among these, hollow-core fibers (HCFs) have attracted significant attention in recent years in the field of terahertz waveguides.…”