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arXiv · 1810.09608

Symmetric supermodes in cyclic multicore fibers

B. Jaramillo Ávila·J. Naya Hernández·S. Ma. Toxqui Rodríguez·B. M. Rodríguez-Lara
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Abstract

Nearest-neighbor coupled-mode theory is a powerful framework to describe electromagnetic-wave propagation in multicore fibers but it lacks precision as the separation between cores decreases. We use abstract symmetries to study a ring of evenly distributed identical cores around a central core, a common configuration used in telecommunications and sensing. We find its normal modes and their effective propagation constants while including the effect of all high-order inter-core couplings. Finite-element simulations support our results to good agreement. Only two of these effective modes involve fields in all the cores. These two modes display opposite-sign phase configurations between the fields in the external cores and the central core. These two modes still appear in the limit where the external cores become a continuous ring. Our results might help improve predictions for crosstalk in telecommunications or precision in sensing applications.

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B. Jaramillo Ávila, J. Naya Hernández, S. Ma. Toxqui Rodríguez, B. M. Rodríguez-Lara. 2018-10-23. Symmetric supermodes in cyclic multicore fibers. https://doi.org/10.1364/osac.2.000515

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