• 文献标题:   Quantum Transport Detected by Strong Proximity Interaction at a Graphene-WS2 van der Waals Interface
  • 文献类型:   Article
  • 作  者:   O FARRELL ECT, AVSAR A, TAN JY, EDA G, OZYILMAZ B
  • 作者关键词:   graphene, ws2, heterostructure, quantum transport, proximity interaction
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Natl Univ Singapore
  • 被引频次:   9
  • DOI:   10.1021/acs.nanolett.5b01128
  • 出版年:   2015

▎ 摘  要

Magnetotransport measurements demonstrate that graphene in a van der Waals heterostructure is a sensitive probe of quantum transport in an adjacent WS2, layer via strong Coulomb interactions. We observe a large low-field magnetoresistance (>> e(2)/h) and a -ln T temperature dependence of the resistance. In-plane magnetic field resistance indicates the origin is orbital and nonclassical. We demonstrate a strong electron hole asymmetry in the mobility and coherence length of graphene demonstrating the presence of localized Coulomb interactions with ionized donors in the WS2, substrate, which ultimately leads to screening as the Fermi level of graphene is tuned toward the conduction band of WS2. This leads us to conclude that graphene couples to quantum localization processes in WS2, via the Coulomb interaction and results in the observed signatures of quantum transport. Our results show that theoretical descriptions of the van der Waals interface should not ignore localized strong correlations.