• 文献标题:   Persistent Topological Surface State at the Interface of Bi2Se3 Film Grown on Patterned Graphene
  • 文献类型:   Article
  • 作  者:   KIM N, LEE P, KIM Y, KIM JS, KIM Y, NOH DY, YU SU, CHUNG J, KIM KS
  • 作者关键词:   topological insulator ti, surface state, bi2se3 thin film, graphene, interface
  • 出版物名称:   ACS NANO
  • ISSN:   1936-0851 EI 1936-086X
  • 通讯作者地址:   Pohang Univ Sci Technol
  • 被引频次:   23
  • DOI:   10.1021/nn405503k
  • 出版年:   2014

▎ 摘  要

We employed graphene as a patternable template to protect the intrinsic surface states of thin films of topological insulators (TIs) from environment. Here we find that the graphene provides high-quality interface so that the Shubnikov de Haas (SdH) oscillation associated with a topological surface state could be observed at the interface of a metallic Bi2Se3 film with a carrier density higher than similar to 10(19) cm(-3). Our in situ X-ray diffraction study shows that the Bi2Se3 film grows epitaxially in a quintuple layer-by-layer fashion from the bottom layer without any structural distortion by interfacial strain. The magnetotransport measurements including SdH oscillations stemming from multiple conductance channels reveal that the topological surface state, with the mobility as high as similar to 0.5 m(2)/(V s), remains intact from the graphene underneath without degradation. Given that the graphene was prepatterned on arbitrary insulating substrates, the TI-based microelectronic design could be exploited. Our study thus provides a step forward to observe the topological surface states at the interface without degradation by tuning the interface between TI and graphene into a measurable current for device application.