You are here

TOPOLOGICAL MATTER Discovery of a Weyl fermion semimetal and topological Fermi arcs

TitleTOPOLOGICAL MATTER Discovery of a Weyl fermion semimetal and topological Fermi arcs
Publication TypeJournal Article
Year of Publication2015
AuthorsXu, Su-Yang, Belopolski Ilya, Alidoust Nasser, Neupane Madhab, Bian Guang, Zhang Chenglong, Sankar Raman, Chang Guoqing, Yuan Zhujun, Lee Chi-Cheng, Huang Shin-Ming, Zheng Hao, Ma Jie, Sanchez Daniel S., Wang BaoKai, Bansil Arun, Chou Fangcheng, Shibayev Pavel P., Lin Hsin, Jia Shuang, and Hasan Zahid M.
Date Published08/2015

A Weyl semimetal is a new state of matter that hosts Weyl fermions as emergent quasiparticles and admits a topological classification that protects Fermi arc surface states on the boundary of a bulk sample. This unusual electronic structure has deep analogies with particle physics and leads to unique topological properties. We report the experimental discovery of a Weyl semimetal, tantalum arsenide (TaAs). Using photoemission spectroscopy, we directly observe Fermi arcs on the surface, as well as the Weyl fermion cones and Weyl nodes in the bulk of TaAs single crystals. We find that Fermi arcs terminate on the Weyl fermion nodes, consistent with their topological character. Our work opens the field for the experimental study of Weyl fermions in physics and materials science.

Theme inspired by Danetsoft