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arXiv · 1603.04323

TaIrTe4 a ternary Type-II Weyl semi-metal

K. Koepernik·D. Kasinathan·D. V. Efremov·Seunghyun Khim·Sergey Borisenko·Bernd Büchner·Jeroen van den Brink
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Abstract

In metallic condensed matter systems two different types of Weyl fermions can in principle emerge, with either a vanishing (type-I) or with a finite (type-II) density of states at the Weyl node energy. So far only WTe2 and MoTe2 were predicted to be type-II Weyl semi-metals. Here we identify TaIrTe4 as a third member of this family of topological semi-metals. TaIrTe4 has the attractive feature that it hosts only four well-separated Weyl points, the minimum imposed by symmetry. Moreover, the resulting topological surface states - Fermi arcs connecting Weyl nodes of opposite chirality - extend to about 1/3 of the surface Brillouin zone. This large momentum-space separation is very favorable for detecting the Fermi arcs spectroscopically and in transport experiments.

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K. Koepernik, D. Kasinathan, D. V. Efremov, Seunghyun Khim, Sergey Borisenko, Bernd Büchner, Jeroen van den Brink. 2016-05-07. TaIrTe4 a ternary Type-II Weyl semi-metal. https://doi.org/10.1103/physrevb.93.201101

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