Analytical formulation for the bend-loss in single-ring hollow-core photonic crystal fibers

Michael H. Frosz; Paul Roth; Mehmet C. Günendi; Philip St. J. Russell

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arXiv · 1611.02581

Analytical formulation for the bend-loss in single-ring hollow-core photonic crystal fibers

Michael H. Frosz·Paul Roth·Mehmet C. Günendi·Philip St. J. Russell

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Abstract

Understanding bend-loss in single-ring hollow-core photonic crystal fibers is becoming of increasing importance as the fibers enter practical applications. While purely numerical approaches are useful, there is a need for a simpler analytical formalism that provides physical insight and can be directly used in the design of PCFs with low bend-loss. We show theoretically and experimentally that a wavelength-dependent critical bend radius exists below which the bend-loss reaches a maximum, and that this can be calculated from the structural parameters of a fiber using a simple analytical formula. This allows straightforward design of single-ring PCFs that are bend-insensitive for specified ranges of bend radius and wavelength. It also can be used to derive an expression for the bend radius that yields optimal higher-order mode suppression for a given fiber structure.

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Michael H. Frosz, Paul Roth, Mehmet C. Günendi, Philip St. J. Russell. 2016-11-08. Analytical formulation for the bend-loss in single-ring hollow-core photonic crystal fibers. https://arxiv.org/abs/1611.02581

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