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Updated: Jun 22, 2026

Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Coupling in dual-core photonic bandgap fibers: theory and experiment
1Centre for Photonics and Photonics Materials, Department of Physics, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
Abstract:
We have theoretically and experimentally investigated dual-core photonic bandgap fibers (PBGFs), which consist of a cladding with an array of high-index rods and two cores formed by omitting two nearby rods. We find novel features in their coupling characteristics such as maxima and minima in coupling length, complete decoupling of the cores, and an inversion of the usual ordering of supermodes so that the odd supermode has the higher propagation constant. This behavior is understood by considering the field distribution in the rods between the cores.
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