Design of photonic crystal fibers with low bending losses

摘要

This paper deals with Photonic Crystal Fibers (PCF) that is not sensitive to bending. On one hand, fiber bending may result in potential negative chromatic dispersion or coupling light from the fundamental mode into the cladding modes, which opens many possibilities to design microstructured optical components for all-optical PCF-based system (group velocity dispersion compensator, bending-induced zero-dispersion fiber, optical filter, optical switch, coupler, photonic crystal cavity with electromagnetically induced transparency etc.) On the other hand, fiber bending is responsible for huge bending losses. The goal of this paper is to reduce bending losses in an operating range of the designed fiber. Reduction of bending losses could be considered as an optimization of the structure that exhibits negative chromatic dispersion and low losses concurrently - then the component is utilizable for many specific applications as dispersion compensator or as an optical switch. Another approach is to design the fiber that would be single-mode for wide range of bending angles or bending radii, but the light is not being coupled into the cladding. Then, no negative chromatic dispersion is produced and the fiber works as a conventional PCF, but not sensitive to bending in an office environment.