• 文献标题:   Valley Hall effect and nonlocal transport in strained graphene
  • 文献类型:   Article
  • 作  者:   ZHANG XP, HUANG CL, CAZALILLA MA
  • 作者关键词:   valley hall effect, transport theory, kinetic equation, hall effect, straintronic
  • 出版物名称:   2D MATERIALS
  • ISSN:   2053-1583
  • 通讯作者地址:   Natl Tsing Hua Univ
  • 被引频次:   11
  • DOI:   10.1088/2053-1583/aa5e9b
  • 出版年:   2017

▎ 摘  要

Graphene subject to high levels of shear strain leads to strong pseudo-magnetic fields resulting in the emergence of pseudo-Landau levels. Here we show that, with modest levels of strain, graphene can also sustain a classical valley Hall effect (VHE) that can be detected in nonlocal transport measurements. We provide a theory of the strain-induced VHE starting from the quantum Boltzmann equation. This allows us to show that, averaging over short-range impurity configurations destroys quantum coherence between valleys, leaving the elastic scattering time and inter-valley scattering rate as the only parameters characterizing the transport theory. Using the theory, we compute the nonlocal resistance of a Hall bar device in the diffusive regime. Our theory is also relevant for the study of moderate strain effects in the (nonlocal) transport properties of other two-dimensional materials and van der Walls heterostructures.