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arXiv · 1909.05051

Bulk and surface electronic structure of the dual-topology semimetal Pt2HgSe3

I. Cucchi·A. Marrazzo·E. Cappelli·S. Ricco·F. Y. Bruno·S. Lisi·M. Hoesch·T. K. Kim·C. Cacho·C. Besnard·E. Giannini·N. Marzari·M. Gibertini·F. Baumberger·A. Tamai
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Abstract

We report high-resolution angle resolved photoemission measurements on single crystals of Pt2HgSe3 grown by high-pressure synthesis. Our data reveal a gapped Dirac nodal line whose (001)-projection separates the surface Brillouin zone in topological and trivial areas. In the non-trivial $k$-space range we find surface states with multiple saddle-points in the dispersion resulting in two van Hove singularities in the surface density of states. Based on density functional theory calculations, we identify these surface states as signatures of a topological crystalline state which coexists with a weak topological phase.

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I. Cucchi, A. Marrazzo, E. Cappelli, S. Ricco, F. Y. Bruno, S. Lisi, M. Hoesch, T. K. Kim, C. Cacho, C. Besnard, E. Giannini, N. Marzari, M. Gibertini, F. Baumberger, A. Tamai. 2019-09-11. Bulk and surface electronic structure of the dual-topology semimetal Pt2HgSe3. https://doi.org/10.1103/physrevlett.124.106402

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