Related Experiment Video
Updated: May 16, 2026

Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Multicorelike guidance in a triangular-core hollow optical fiber and spectral evolution of its eigenmode degeneracy
Sejin Lee1, Woosung Ha, Jens Kobelke
1Institute of Physics and Applied Physics, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, South Korea.
Abstract:
A unique multicorelike guidance was achieved in a microstructured optical fiber composed of a circular air hole at the center surrounded by a high-index triangular core. Unique spectral evolution of the degeneracy was theoretically investigated using a vectorial finite element method to find a threefold degeneracy in both the fundamental and the first excited modes in the visible range, which evolved to twofold degeneracy as the wavelength increased to IR. Experimental measurements also confirmed evolution of the modal intensity from three spatially isolated patterns confined to individual corners into a supermode combining the three corners.
Related Concept Videos
IR Spectrum Peak Splitting: Symmetric vs Asymmetric Vibrations
Interference and Diffraction
Fermi Level Dynamics
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
IR Absorption Frequency: Delocalization
In IR spectroscopy,...
Symmetry in Maxwell's Equations
¹H NMR Signal Multiplicity: Splitting Patterns

