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arXiv · 1805.11791

Hopf-chain networks evolved from triple points

Yuee Xie·Jin Cai·Jinwoong Kim·Po-Yao Chang·Yuanping Chen
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Abstract

Exotic links and chains attract interests across various disciplines including mathematics, biology, chemistry and physics. Here, we propose that topological Hopf-chain networks, consisting of one-, two- and three-dimensional (3D) Hopf chains, can be found in the momentum space. These networks can be evolved from a 3D triple-points phase by varying symmetries of a four-band model. Moreover, we identify that the Hopf-chain networks exist in a family of crystals Sc3XC (X = Al, Ga, In, Tl). The crystals are 3D triple-points metals, and transit to topological metals with Hopf-chain networks under strains. These novel Hopf networks exhibit unique Landau levels and magneto-transport properties.

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Yuee Xie, Jin Cai, Jinwoong Kim, Po-Yao Chang, Yuanping Chen. 2019-04-21. Hopf-chain networks evolved from triple points. https://doi.org/10.1103/physrevb.99.165147

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