Open AccessCompact three-core fibers with ultra-low differential group delays for broadband mode-division multiplexing
Author(s) -
Yunfei Wu,
Kin Seng Chiang
Publication year - 2015
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.23.020867
Subject(s) - cladding (metalworking) , broadband , optics , differential group delay , multiplexing , wavelength division multiplexing , core (optical fiber) , multi mode optical fiber , graded index fiber , dispersion shifted fiber , optical fiber , materials science , physics , polarization mode dispersion , wavelength , telecommunications , fiber optic sensor , computer science , metallurgy
An approximate explicit condition for the achievement of zero differential group delay (DGD) in a homogeneous multicore fiber (MCF) is presented and verified numerically for a step-index three-core fiber. This condition is explored for the study of compact three-core fibers with low DGDs. To achieve an ultra-low DGD in the C-band, a three-core fiber with a central refractive-index dip in each core is proposed and analyzed in detail. A specific design with three touching cores and a core-cladding index difference of 0.3% yields a maximum DGD smaller than 3.2 ps/km in the C-band. The fiber is suitable for broadband mode-division multiplexing applications and the design approach could be applied to MCFs with more cores.