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arXiv · 1712.09502

Near-zero index magneto-optical medium realized with an unpaired Dirac point

Xin Zhou·Daniel Leykam·A. B. Khanikaev·Y. D. Chong
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Abstract

We realize an unpaired Dirac cone at the center of the first Brillouin zone, using a gyromagnetic photonic crystal with broken square sub-lattice symmetry and broken time reversal symmetry. The behavior of the Dirac modes can be described by a gyromagnetic effective medium model with near-zero refractive index, and Voigt parameter near unity. When two domains are subjected to opposite magnetic biases, there exist unidirectional edge states along the domain wall. This establishes a link between topological edge states and the surface waves of homogenous magneto-optical media.

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Xin Zhou, Daniel Leykam, A. B. Khanikaev, Y. D. Chong. 2017-12-27. Near-zero index magneto-optical medium realized with an unpaired Dirac point. https://doi.org/10.1103/physrevb.98.205115

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