title: Topological spin texture in a quantum anomalous Hall insulator.
abstract: The quantum anomalous Hall (QAH) effect has been recently discovered in an experiment using a thin-film topological insulator with ferromagnetic ordering and strong spin-orbit coupling. Here we investigate the spin degree of freedom of a QAH insulator and uncover the fundamental phenomenon that the edge states exhibit a topologically stable spin texture in the boundary when a chiral-like symmetry is present. This result shows that edge states are chiral in both the orbital and spin degrees of freedom, and the chiral edge spin texture corresponds to the bulk topological states of the QAH insulator. We also study the potential applications of the edge spin texture in designing topological-state-based spin devices, which might be applicable to future spintronic technologies.
authors.affiliation: Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China and Department of Physics, South University of Science and Technology of China, Shenzhen 518055, China.
authors.forename: Jiansheng
authors.initials: J
authors.lastname: Wu
authors.affiliation: Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China and International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, China and Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: Xiong-Jun
authors.initials: XJ
authors.lastname: Liu