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arXiv · 1704.01948

Weyl-link semimetals

Po-Yao Chang·Chuck-Hou Yee
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Abstract

A family of topological semimetallic phases where twofold degenerate gapless points form linked rings is introduced. We refer to this phase as Weyl-link semimetals. A concrete two-band model with two linked nodal lines is constructed. We demonstrate that the Chern-Simons 3-form depends on the linking number of rings in a generic two-band model. In addition, we show the emergence of zero-energy modes in the Landau level spectrum can reveal the location of nodal lines, providing a method of probing their linking number.

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Po-Yao Chang, Chuck-Hou Yee. 2017-08-24. Weyl-link semimetals. https://doi.org/10.1103/physrevb.96.081114

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