Abstract
In this paper, we numerically investigate various hollow-core anti-resonant (HC-AR) fibers towards low propagation and bend loss with effectively single-mode operation in the telecommunications window. We demonstrate how the propagation loss and higher-order mode modal contents are strongly influenced by the geometrical structure and the number of the anti-resonant cladding tubes. We found that 5-tube nested HC-AR fiber has a wider anti-resonant band, lower loss, and larger higher-order mode extinction ratio than designs with 6 or more anti-resonant tubes. A loss ratio between the higher-order modes and fundamental mode, as high as 12,000, is obtained in a 5-tube nested HC-AR fiber. To the best of our knowledge, this is the largest higher-order mode extinction ratio demonstrated in a hollow-core fiber at 1.55 μm. In addition, we propose a modified 5-tube nested HC-AR fiber, with propagation loss below 1 dB/km from 1330 to 1660 nm. This fiber also has a small bend loss of ~15 dB/km for a bend radius of 1 cm.
Highlights
Hollow-core fibers have been extensively studied and fabricated by several research groups around the globe over the past two decades due to their extraordinary ability of light guidance in an air-core [1,2,3,4,5,6,7,8,9]
In this paper, we numerically investigate various hollow-core anti-resonant (HCAR) fibers towards low propagation and bend loss with effectively single-mode operation in the telecommunications window
We demonstrate that details of the cladding structure and the number of anti-resonant cladding tubes significantly affects the propagation loss and single-mode operation
Summary
Hollow-core fibers have been extensively studied and fabricated by several research groups around the globe over the past two decades due to their extraordinary ability of light guidance in an air-core [1,2,3,4,5,6,7,8,9]. Hollow-core photonic bandgap (HC-PBG) fiber, light is guided inside the air-core via PBG effect [1] In these fibers, the cladding does not support modes for certain ranges of optical wavelengths and propagation constants modes confining the light with low loss. The other class of hollow-core fiber is typically referred to as “inhibited coupling” fibers In these structures, light guidance is supported via inhibited coupling between the core guided modes and a continuum of cladding modes [30,31]. Light guidance is supported via inhibited coupling between the core guided modes and a continuum of cladding modes [30,31] These fibers have sparked great interest owing to its remarkable transmission properties such as broad bandwidth, very low power overlap with the glass regions, low dispersion, and low loss levels.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
