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arXiv · 1207.0478

Weyl points and line nodes in gapless gyroid photonic crystals

Ling Lu·Liang Fu·John D. Joannopoulos·Marin Soljačić
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Abstract

Weyl points and line nodes are three-dimensional linear point- and line-degeneracies between two bands. In contrast to Dirac points, which are their two-dimensional analogues, Weyl points are stable in the momentum space and the associated surface states are predicted to be topologically non-trivial. However, Weyl points are yet to be discovered in nature. Here, we report photonic crystals, based on the double-gyroid structures, exhibiting frequency-isolated Weyl points with intricate phase diagrams. The surface states associated with the non-zero Chern numbers are demonstrated. Line nodes are also found in similar geometries; the associated surface states are shown to be flat bands. Our results are readily experimentally realizable at both microwave and optical frequencies.

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Ling Lu, Liang Fu, John D. Joannopoulos, Marin Soljačić. 2012-07-02. Weyl points and line nodes in gapless gyroid photonic crystals. https://doi.org/10.1038/nphoton.2013.42

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