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arXiv · 1608.04602

Heavy Weyl fermion state in CeRu$_4$Sn$_6$

Yuanfeng Xu·Changming Yue·Hongming Weng·Xi Dai
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Abstract

A new type of topological state in strongly corrected condensed matter systems, heavy Weyl fermion state, has been found in a heavy fermion material CeRu$_4$Sn$_6$, which has no inversion symmetry. Both two different types of Weyl points, type I and II, can be found in the quasi-particle band structure obtained by the LDA+Guztwiller calculations, which can treat the strong correlation effects among the f-electrons from Cerium atoms. The surface calculations indicate that the topologically protected Fermi arc states exist on the (010) but not on the (001) surfaces.

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Yuanfeng Xu, Changming Yue, Hongming Weng, Xi Dai. 2016-08-16. Heavy Weyl fermion state in CeRu$_4$Sn$_6$. https://doi.org/10.1103/physrevx.7.011027

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