Open AccessSeven air-core fibers with germanium-doped high-index rings supporting hundreds of OAM modes
Author(s) -
Yingning Wang,
Kunbi Zhu,
Wenqian Zhao,
Wenpu Geng,
Yuxi Fang,
Changjing Bao,
Yongxiong Ren,
Hao Zeng,
Weigang Zhang,
Zhongqi Pan,
Yang Yue
Publication year - 2021
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.431314
Subject(s) - optics , crosstalk , physics , angular momentum , optical fiber , core (optical fiber) , graded index fiber , mode volume , modal , refractive index , optical communication , materials science , fiber optic sensor , quantum mechanics , polymer chemistry
In this paper, we propose and design a multi-orbital-angular-momentum multi-ring air-core fiber, which has seven high-index rings with each ring supporting 62 radially fundamental OAM modes across C and L bands (from 1530 nm to 1625 nm), i.e. 434 OAM modes in total. The designed fiber features >4×10 -4 intra-ring modal indices difference for OAM modes with the same topological charge l in a ring across the C and L bands. Moreover, it can keep <-52 dB crosstalk between the OAM modes in the adjacent rings at 1550 nm, and <-24 dB crosstalk across C and L bands after 100-km fiber propagation. This kind of seven-air-core-ring fiber would be a robust candidate for transmitting efficient OAM modes and boosting the capacity of optical fiber communications systems.