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arXiv · 1502.01879

Composite multi-vortex diffraction-free beams and van Hove singularities in honeycomb lattices

Vassilis Paltoglou·Zhigang Chen·Nikolaos K. Efremidis
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Abstract

We find diffraction-free beams for graphene and MoS$_2$-type honeycomb optical lattices. The resulting composite solutions have the form of multi-vortices, with spinor topological charges ($n$, $n\pm1$). Exact solutions for the spinor components are obtained in the Dirac limit. The effects of the valley degree of freedom and the mass are analyzed. Passing through the van-Hove singularity the topological structure of the solutions is modified. Exactly at the singularity the diffraction-free beams take the form of strongly localized one-dimensional stripes.

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Vassilis Paltoglou, Zhigang Chen, Nikolaos K. Efremidis. 2015-02-06. Composite multi-vortex diffraction-free beams and van Hove singularities in honeycomb lattices. https://doi.org/10.1364/ol.40.001037

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