• 文献标题:   Single-parameter quantum valley pumping in graphene with topological line defect
  • 文献类型:   Article
  • 作  者:   REN CD, ZHOU BH, LU WT, GU Y, TIAN HY
  • 作者关键词:   line defect, graphene, singleparameter quantum valley pumping
  • 出版物名称:   RESULTS IN PHYSICS
  • ISSN:   2211-3797
  • 通讯作者地址:   Linyi Univ
  • 被引频次:   0
  • DOI:   10.1016/j.rinp.2020.103138
  • 出版年:   2020

▎ 摘  要

We report a theoretical study of single-parameter quantum valley pumping in graphene with a topological line defect via the Keldysh Green's function method. It is found that the valley pumping currents appear only at large scattering angles, with the negative sign for K valley while positive sign for K' valley. The currents following along the direction of the line defect can reach up to 0.1 mA over a large range of Fermi energies and the driving frequencies of an ac-field, which is beneficial for applications. The high currents origin from the asymmetric scattering in the photon-assisted processes and the special characteristics of electronic state distribution in the line defect. In the case of ferromagnetic lead, the two spin currents flow into different leads, respectively.