2017/06/02 by Mingda Li, Qichen Song, Weiwei Zhao +13 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Electron #Fermi level #Ferromagnetism #Graphene research and applications #Heterojunction #Insulator (electricity) #Magnetism #Optoelectronics #Physics #Quantum mechanics #Spintronics #Topological Materials and Phenomena #Topological insulator #Topology (electrical circuits) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.96.201301
published as Phys. Rev. B 96, 201301 (2017) · 5 pages main text with 4 figures; 2 pages supplemental materials; suggestions and discussions are welcomed
arxiv created 2017/06/02 · openalex created_date 2017/06/15 · openalex publication_date 2017/11/01 · arxiv updated 2017/11/08 · openalex updated_date 2026/08/06
The possible realization of dissipationless chiral edge current in a topological insulator/magnetic insulator heterostructure is based on the condition that the magnetic proximity exchange coupling at the interface is dominated by the Dirac surface states of the topological insulator. Here we report a polarized neutron reflectometry observation of Dirac-electron-mediated magnetic proximity effect in a bulk-insulating topological insulator (Bi0.2Sb0.8)2Te3/magnetic insulator EuS heterostructure. We are able to maximize the proximity-induced magnetism by applying an electrical back gate to tune the Fermi level of topological insulator to be close to the Dirac point. A phenomenological model based on diamagnetic screening is developed to explain the suppressed proximity-induced magnetism at high carrier density. Our work paves the way to utilize the magnetic proximity effect at the topological insulator/magnetic insulator heterointerface for low-power spintronic applications.