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arXiv · 1706.06030

A group theoretical route to deterministic Weyl points in chiral photonic lattices

Matthias Saba·Joachim M. Hamm·Jeremy J. Baumberg·Ortwin Hess
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Abstract

Classical topological phases derived from point degeneracies in photonic bandstructures show intriguing and unique behaviour. Previously identified exceptional points are based on accidental degeneracies and subject to engineering on a case-by-case basis. Here we show that symmetry induced (deterministic) pseudo Weyl points with non-trivial topology and hyper-conic dispersion exist at the centre of the Brillouin zone of chiral cubic systems. We establish the physical implications by means of a $P2_13$ sphere packing, realised as a nano plasmonic system and a photonic crystal.

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Matthias Saba, Joachim M. Hamm, Jeremy J. Baumberg, Ortwin Hess. 2017-06-19. A group theoretical route to deterministic Weyl points in chiral photonic lattices. https://doi.org/10.1103/physrevlett.119.227401

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