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arXiv · 1703.04242

Experimental evidence of type-II Dirac fermions in PtSe2

Kenan Zhang·Mingzhe Yan·Haoxiong Zhang·Huaqing Huang·Masashi Arita·Zhe Sun·Wenhui Duan·Yang Wu·Shuyun Zhou
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Abstract

Topological semimetals have attracted extensive research interests for realizing condensed matter physics counterparts of three-dimensional Dirac and Weyl fermions, which were originally introduced in high energy physics. Recently it has been proposed that type-II Dirac semimetal can host a new type of Dirac fermions which break Lorentz invariance and therefore does not have counterpart in high energy physics. Here we report the electronic structure of high quality PtSe$_2$ crystals to provide direct evidence for the existence of three-dimensional type-II Dirac fermions. A comparison of the crystal, vibrational and electronic structure to a sister compound PtTe$_2$ is also discussed. Our work provides an important platform for exploring the novel quantum phenomena in the PtSe$_2$ class of type-II Dirac semimetals.

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Kenan Zhang, Mingzhe Yan, Haoxiong Zhang, Huaqing Huang, Masashi Arita, Zhe Sun, Wenhui Duan, Yang Wu, Shuyun Zhou. 2017-03-13. Experimental evidence of type-II Dirac fermions in PtSe2. https://doi.org/10.1103/physrevb.96.125102

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