Dirac nodal lines in the quasi-one-dimensional ternary telluride TaPtTe\(_5\)

• Published in: arXiv.org 2022-05
• Main Authors: Xiao, Shaozhu, Wen-He, Jiao, Lin, Yu, Jiang, Qi, Yang, Xiufu, He, Yunpeng, Jiang, Zhicheng, Yang, Yichen, Liu, Zhengtai, Mao Ye, Shen, Dawei, He, Shaolong
• Format: Article
• Language: English
• Subjects: Brillouin zones; Electronic structure; First principles; Intermetallic compounds; Photoelectric emission; Spin-orbit interactions; Symmetry; Tellurides; Two dimensional materials
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2205.05852

A Dirac nodal-line phase, as a quantum state of topological materials, usually occur in three-dimensional or at least two-dimensional materials with sufficient symmetry operations that could protect the Dirac band crossings. Here, we report a combined theoretical and experimental study on the electronic structure of the quasi-one-dimensional ternary telluride TaPtTe\(_5\), which is corroborated as being in a robust nodal-line phase with fourfold degeneracy. Our angle-resolved photoemission spectroscopy measurements show that two pairs of linearly dispersive Dirac-like bands exist in a very large energy window, which extend from a binding energy of \(\sim\) 0.75 eV to across the Fermi level. The crossing points are at the boundary of Brillouin zone and form Dirac-like nodal lines. Using first-principles calculations, we demonstrate the existing of nodal surfaces on the \(k_y = \pm \pi\) plane in the absence of spin-orbit coupling (SOC), which are protected by nonsymmorphic symmetry in TaPtTe\(_5\). When SOC is included, the nodal surfaces are broken into several nodal lines. By theoretical analysis, we conclude that the nodal lines along \(Y\)-\(T\) and the ones connecting the \(R\) points are non-trivial and protected by nonsymmorphic symmetry against SOC.