A possible candidate for triply degenerate point fermions in trigonal layered PtBi2

• DOI: 10.1038/s41467-018-05730-3
• Publication Date: 2018-08-08T10:20:18Z
• Authors: Wenshuai Gao; Xiangde Zhu; Fawei Zheng; Min Wu; Jinglei Zhang; Chuanying Xi; Ping Zhang; Yuheng Zhang; Ning Hao; Wei Ning; Mingliang Tian
• Keywords: Fermi energy

Triply degenerate point (TP) fermions in tungsten-carbide-type materials (e.g., MoP), which represent new topological states of quantum matter, have generated immense interest recently. However, the TPs these are found to be far below Fermi level, leading TP having less contribution low-energy quasiparticle excitations. Here, we theoretically predict existence with points close level trigonal layered PtBi2 by ab initio calculations, and experimentally verify predicted band topology magnetotransport measurements under high magnetic fields up 40 T. Analyses both pronounced Shubnikov-de Haas de Haas-van Alphen oscillations reveal six principal pockets. Our experimental results, together those from interplay between transport behaviors unique electronic structures, support PtBi2.