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arXiv · 1703.01136

Band splitting and Weyl nodes in trigonal tellurium studied by angle-resolved photoemission spectroscopy and density functional theory

K. Nakayama·M. Kuno·K. Yamauchi·S. Souma·K. Sugawara·T. Oguchi·T. Sato·T. Takahashi
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Abstract

We have performed high-resolution angle-resolved photoemission spectroscopy (ARPES) on trigonal tellurium consisting of helical chains in the crystal. Through the band-structure mapping in the three-dimensional Brillouin zone, we found a definitive evidence for the band splitting originating from the chiral nature of crystal. A direct comparison of the band dispersion between the ARPES results and the first-principles band-structure calculations suggests the presence of Weyl nodes and tiny spin-polarized hole pockets around the H point. The present result opens a pathway toward studying the interplay among crystal symmetry, band structure, and exotic physical properties in chiral crystals.

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K. Nakayama, M. Kuno, K. Yamauchi, S. Souma, K. Sugawara, T. Oguchi, T. Sato, T. Takahashi. 2017-03-29. Band splitting and Weyl nodes in trigonal tellurium studied by angle-resolved photoemission spectroscopy and density functional theory. https://doi.org/10.1103/physrevb.95.125204

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