Topological nodal-line fermions in spin-orbit metal PbTaSe2

Guang Bian, Tay Rong Chang, Raman Sankar, Su Yang Xu, Hao Zheng, Titus Neupert, Ching Kai Chiu, Shin Ming Huang, Guoqing Chang, Ilya Belopolski, Daniel S. Sanchez, Madhab Neupane, Nasser Alidoust, Chang Liu, Bao Kai Wang, Chi Cheng Lee, Horng Tay Jeng, Chenglong Zhang, Zhujun Yuan, Shuang JiaArun Bansil, Fangcheng Chou, Hsin Lin, M. Zahid Hasan

Research output: Contribution to journalArticlepeer-review

695 Scopus citations


Topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems.

Original languageEnglish (US)
Article number10556
JournalNature communications
StatePublished - Feb 2 2016

All Science Journal Classification (ASJC) codes

  • General Chemistry
  • General Biochemistry, Genetics and Molecular Biology
  • General Physics and Astronomy


Dive into the research topics of 'Topological nodal-line fermions in spin-orbit metal PbTaSe2'. Together they form a unique fingerprint.

Cite this