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arXiv · 1807.08806

Excitation of higher-order modes in optofluidic photonic crystal fiber

Andrei Ruskuc·Philipp Koehler·Marius A. Weber·Ana Andres-Arroyo·Michael H. Frosz·Philip St. J. Russell·Tijmen G. Euser
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Abstract

Higher-order modes up to LP$_{33}$ are controllably excited in water-filled kagomé- and bandgap-style hollow-core photonic crystal fibers (HC-PCF). A spatial light modulator is used to create amplitude and phase distributions that closely match those of the fiber modes, resulting in typical launch efficiencies of 10-20% into the liquid-filled core. Modes, excited across the visible wavelength range, closely resemble those observed in air-filled kagomé HC-PCF and match numerical simulations. Mode indices are obtained by launching plane-waves at specific angles onto the fiber input-face and comparing the resulting intensity pattern to that of a particular mode. These results provide a framework for spatially-resolved sensing in HC-PCF microreactors and fiber-based optical manipulation.

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Andrei Ruskuc, Philipp Koehler, Marius A. Weber, Ana Andres-Arroyo, Michael H. Frosz, Philip St. J. Russell, Tijmen G. Euser. 2018-07-23. Excitation of higher-order modes in optofluidic photonic crystal fiber. https://doi.org/10.1364/oe.26.030245

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