• 文献标题:   Counterintuitive gate dependence of weak antilocalization in bilayer graphene/WSe2 heterostructures
  • 文献类型:   Article
  • 作  者:   AMANN J, VOLKL T, ROCKINGER T, KOCHAN D, WATANABE K, TANIGUCHI T, FABIAN J, WEISS D, EROMS J
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:  
  • 被引频次:   7
  • DOI:   10.1103/PhysRevB.105.115425
  • 出版年:   2022

▎ 摘  要

Strong gate control of proximity-induced spin-orbit coupling was recently predicted in bilayer graphene/transition metal dichalcogenide (BLG/TMDC) heterostructures, as charge carriers can easily be shifted between the two graphene layers, and only one of them is in close contact to the TMDC. The presence of spin-orbit coupling can be probed by weak antilocalization (WAL) in low-field magnetotransport measurements. When the spin-orbit splitting in such a heterostructure increases with the out-of-plane electric displacement field (D) over bar, one intuitively expects a concomitant increase of WAL visibility. Our experiments show that this is not the case. Instead, we observe a maximum of WAL visibility around (D) over bar = 0. This counterintuitive behavior originates in the intricate dependence of WAL in graphene on symmetric and antisymmetric spin lifetimes, caused by the valley-Zeeman and Rashba terms, respectively. Our observations are confirmed by calculating spin precession and spin lifetimes from an 8 x 8 model Hamiltonian of BLG/TMDC.