• 文献标题:   Current splitting and valley polarization in elastically deformed graphene
  • 文献类型:   Article
  • 作  者:   STEGMANN T, SZPAK N
  • 作者关键词:   deformed graphene, valleytronic, device physic
  • 出版物名称:   2D MATERIALS
  • ISSN:   2053-1583
  • 通讯作者地址:   Univ Nacl Autonoma Mexico
  • 被引频次:   17
  • DOI:   10.1088/2053-1583/aaea8d
  • 出版年:   2019

▎ 摘  要

Elastic deformations of graphene can significantly change the flow paths and valley polarization of the electric currents. We investigate these phenomena in graphene nanoribbons with localized out-of-plane deformations by means of tight-binding transport calculations. Such deformations can split the current into two beams of almost completely valley polarized electrons and give rise to a valley voltage. These properties are observed for a fairly wide set of experimentally accessible parameters. We propose a valleytronic nanodev ice in which a high polarization of the electrons comes along with a high transmission making the device very efficient. In order to gain a better understanding of these effects, we also treat the system in the continuum limit in which the electronic excitations can be described by the Dirac equation coupled to curvature and a pseudo-magnetic field. Semiclassical trajectories offer then an additional insight into the balance of forces acting on the electrons and provide a convenient tool for predicting the behavior of the current flow paths. The proposed device can also be used for a sensitive measurement of graphene deformations.