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Small-core photonic crystal fibers with weakly disordered air-hole claddings

N. A. Mortensen·M. D. Nielsen·J. R. Folkenberg·K. P. Hansen·J. Laegsgaard
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Abstract

Motivated by recent experimental work by Folkenberg et al. we consider the effect of weak disorder in the air-hole lattice of small-core photonic crystal fibers. We find that the broken symmetry leads to higher-order modes which have generic intensity distributions resembling those found in standard fibers with elliptical cores. This explains why recently reported experimental higher-order mode profiles appear very different from those calculated numerically for ideal photonic crystal fibers with inversion and six-fold rotational symmetry. The splitting of the four higher-order modes into two groups fully correlates with the observation that these modes have different cut-offs.

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N. A. Mortensen, M. D. Nielsen, J. R. Folkenberg, K. P. Hansen, J. Laegsgaard. 2003-11-21. Small-core photonic crystal fibers with weakly disordered air-hole claddings. https://doi.org/10.1088/1464-4258%2F6%2F2%2F011

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