• 文献标题:   Nanoscale strain engineering of giant pseudo-magnetic fields, valley polarization, and topological channels in graphene
  • 文献类型:   Article
  • 作  者:   HSU CC, TEAGUE ML, WANG JQ, YEH NC
  • 作者关键词:  
  • 出版物名称:   SCIENCE ADVANCES
  • ISSN:   2375-2548
  • 通讯作者地址:   CALTECH
  • 被引频次:   5
  • DOI:   10.1126/sciadv.aat9488
  • 出版年:   2020

▎ 摘  要

The existence of nontrivial Berry phases associated with two inequivalent valleys in graphene provides interesting opportunities for investigating the valley-projected topological states. Examples of such studies include observation of anomalous quantum Hall effect in monolayer graphene, demonstration of topological zero modes in "molecular graphene" assembled by scanning tunneling microscopy, and detection of topological valley transport either in graphene superlattices or at bilayer graphene domain walls. However, all aforementioned experiments involved nonscalable approaches of either mechanically exfoliated flakes or atom-by-atom constructions. Here, we report an approach to manipulating the topological states in monolayer graphene via nanoscale strain engineering at room temperature. By placing strain-free monolayer graphene on architected nanostructures to induce global inversion symmetry breaking, we demonstrate the development of giant pseudo-magnetic fields (up to similar to 800 T), valley polarization, and periodic one-dimensional topological channels for protected propagation of chiral modes in strained graphene, thus paving a pathway toward scalable graphene-based valleytronics.