16. November 2015

Observation of Fermi-Arc Spin Texture in TaAs

The study of nontrivial topological semimetals (TSM) is an emerging subject, providing a new frontier in topological aspects beyond insulators. Here, we have investigated the spin texture of surface Fermi arcs in the recently discovered Weyl semimetal TaAs using spin- and angle-resolved photoemission spectroscopy. The experimental results demonstrate that the Fermi arcs are spin polarized. The measured spin texture fulfills the requirement of mirror and time-reversal symmetries and is well reproduced by our first-principles calculations, which gives strong evidence for the topologically nontrivial Weyl semimetal state in TaAs. The consistency between the experimental and calculated results further confirms the distribution of chirality of the Weyl nodes determined by first principles calculations.
PSI Media Release
Electron’s cousin discovered after eighty-six-year search
Original Publication
Observation of Fermi-Arc Spin Texture in TaAs
B. Q. Lv, S. Muff, T. Qian, Z. D. Song, S. M. Nie, N. Xu, P. Richard, C. E. Matt, N. C. Plumb, L. X. Zhao, G. F. Chen, Z. Fang, X. Dai, J. H. Dil, J. Mesot, M. Shi, H. M. Weng and H. Ding
Phys. Rev. Lett. 115, 217601 (2015), published 16 November 2015, DOI: 10.1103/PhysRevLett.115.217601
Prof. Dr Ming Shi
Spectroscopy of Novel Materials Group
Laboratory for Synchrotron Radiation — Condensed Matter Physics
Swiss Light Source, Paul Scherrer Institute
5232 Villigen PSI, Switzerland
Phone: +41 56 310 2393, e-mail: ming.shi@psi.ch