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arXiv · 2007.05068

Higher-Order Weyl Semimetals

Hai-Xiao Wang·Zhi-Kang Lin·Bin Jiang·Guang-Yu Guo·Jian-Hua Jiang
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Abstract

Higher-order topology yields intriguing multidimensional topological phenomena, while Weyl semimetals have unconventional properties such as chiral anomaly. However, so far, Weyl physics remain disconnected with higher-order topology. Here, we report the theoretical discovery of higher-order Weyl points and thereby the establishment of such an important connection. We demonstrate that higher-order Weyl points can emerge in chiral materials such as chiral tetragonal crystals as the intermediate phase between the conventional Weyl semimetal and 3D higher-order topological phases. Higher-order Weyl semimetals manifest themselves uniquely by exhibiting concurrent chiral Fermi-arc surface states, topological hinge states, and the momentum-dependent fractional hinge charge, revealing a novel class of higher-order topological phases.

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Hai-Xiao Wang, Zhi-Kang Lin, Bin Jiang, Guang-Yu Guo, Jian-Hua Jiang. 2020-07-09. Higher-Order Weyl Semimetals. https://doi.org/10.1103/physrevlett.125.146401

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