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arXiv · 1703.09899

Type-II Dirac Photons

Hai-Xiao Wang·Yige Chen·Zhi Hong Hang·Hae-Young Kee·Jian-Hua Jiang
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Abstract

The Dirac equation for relativistic electron waves is the parent model for Weyl and Majorana fermions as well as topological insulators. Simulation of Dirac physics in three-dimensional photonic crystals, though fundamentally important for topological phenomena at optical frequencies, encounters the challenge of synthesis of both Kramers double degeneracy and parity inversion. Here we show how type-II Dirac points---exotic Dirac relativistic waves yet to be discovered---are robustly realized through the nonsymmorphic screw symmetry. The emergent type-II Dirac points carry nontrivial topology and are the mother states of type-II Weyl points. The proposed all-dielectric architecture enables robust cavity states at photonic-crystal---air interfaces and anomalous refraction, with very low energy dissipation.

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Hai-Xiao Wang, Yige Chen, Zhi Hong Hang, Hae-Young Kee, Jian-Hua Jiang. 2017-03-29. Type-II Dirac Photons. https://doi.org/10.1038/s41535-017-0058-z

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