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arXiv · 2608.10683

Stability of Orbital Angular Momentum Modes in Conventional and Ring-Core Optical Fibers

Hassan Asgharzadeh B.·Regina Gumenyuk·Marco Ornigotti
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Abstract

Modal dynamics in multimode optical fibers are fundamentally governed by the inter- play between phase matching and intermodal coupling. In this work, we investigate the fundamental coupling mechanisms in ring-core fibers and identify a geometry-induced cou- pling suppression that significantly reduces coupling coefficients between orbital angular momentum modes compared to conventional multimode step-index fibers. This mechanism provides a clear physical explanation for the superior transmission stability of orbital angular momentum modes in ring-core fibers and establishes specific geometric constraints for the design of ring-core fiber-based mode converters.

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Hassan Asgharzadeh B., Regina Gumenyuk, Marco Ornigotti. 2026-08-11. Stability of Orbital Angular Momentum Modes in Conventional and Ring-Core Optical Fibers. https://arxiv.org/abs/2608.10683

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