2020/06/30 by Xi Zhang, Qiangqiang Gu, Haigen Sun +20
Materials Science · Mathematics · Physics and Astronomy · #2D Materials and Applications #Charge density wave #Condensed matter physics #Degenerate energy levels #Electronic band structure #Excitation #Geometry #Ground state #Homogeneous space #Lattice (music) #Mathematics #Organic and Molecular Conductors Research #Physics #Point reflection #Quantum mechanics #Quasiparticle #Topological Materials and Phenomena #Topology (electrical circuits) #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.102.035125
published as Phys. Rev. B 102, 035125 (2020) · Accepted by PRB: https://journals.aps.org/prb/accepted/7907cK4eW0b1ee0b93fd67c1b42942bbb08eafc3c
arxiv created 2020/06/30 · openalex publication_date 2020/07/14 · arxiv updated 2020/07/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The 230 space group symmetries of three-dimensional crystal lattices permit the existence of quasiparticle excitations beyond the standard model of high-energy physics. Here, the authors propose that the TaTe4 crystal, with a quasi-one-dimensional lattice structure, holds an eightfold degenerate double Dirac point and a fourfold degenerate Dirac point in the charge density wave (CDW) ground state. The calculated band structure is consistent with Shubnikov--de Haas oscillation measurements. Further, an atomic step edge state is detected, suggesting nontrivial topology. This work reveals the CDW-induced topological phases and provides new insight into the interplay between the CDW and fermionic excitations.