• 文献标题:   Global Control of Stacking-Order Phase Transition by Doping and Electric Field in Few-Layer Graphene
  • 文献类型:   Article
  • 作  者:   LI HY, UTAMA MIB, WANG S, ZHAO WY, ZHAO SH, XIAO X, JIANG Y, JIANG LL, TANIGUCHI T, WATANABE K, WEBERBARGIONI A, ZETTL A, WANG F
  • 作者关键词:   graphene, aba/abc stacking, stacking phase transition, lowdimensional material
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Univ Calif Berkeley
  • 被引频次:   3
  • DOI:   10.1021/acs.nanolett.9b05092
  • 出版年:   2020

▎ 摘  要

The layer stacking order has profound effects on the physical properties of two-dimensional van der Waals heterostructures. For example, graphene multilayers can have distinct electronic band structures and exhibit completely different behaviors depending on the stacking order. Fascinating physical phenomena, such as correlated insulators, superconductors, and ferromagnetism, can also emerge with a periodic variation of the layer stacking order, which is known as the moire superlattice in van der Waals materials. In this work, we realize the global phase transition between different graphene layer stacking orders and elucidate its microscopic origin. We experimentally determine the energy difference between different stacking orders with the accuracy of mu eV/atom. We reveal that both the carrier doping and the electric field can drive the layer-stacking phase transition through different mechanisms: carrier doping can change the energy difference because of a non-negligible work function difference between different stacking orders; the electric field, on the other hand, induces a band-gap opening in ABC-stacked graphene and hence changes the energy difference. Our findings provide a fundamental understanding of the electrically driven stacking-order phase transition in few-layer graphene and demonstrate a reversible and noninvasive method to globally control the stacking order.