AVS 61st International Symposium & Exhibition
    Scanning Probe Microscopy Focus Topic Thursday Sessions
       Session SP+2D+AS+EM+MC+NS+SS-ThM

Paper SP+2D+AS+EM+MC+NS+SS-ThM11
Coherent One Dimensional Boundaries in Graphene and Hexagonal Boron Nitride Heterostructures

Thursday, November 13, 2014, 11:20 am, Room 312

Session: Probing Electronic and Transport Properties
Presenter: Jewook Park, Oak Ridge National Laboratory
Authors: J. Park, Oak Ridge National Laboratory
L. Liu, The University of Tennessee Knoxville
D.A. Siegel, Sandia National Laboratories
K.F. McCarty, Sandia National Laboratories
L. Basile, ORNL
J.-C. Idrobo, ORNL
K. Clark, ORNL
W. Deng, The Univ. of Tennessee Knoxville
C.P. Durand, ORNL
G. Gu, The Univ. of Tennessee Knoxville
A.P. Li, ORNL
Correspondent: Click to Email
The quest for novel two-dimensional (2D) materials has led to the discovery of hybrid heterostructures where graphene and other atomic layer films such as monolayer hexagonal boron nitride (hBN) form phase-separated domains or both materials grow epitaxially onto a common crystalline substrate. By implementing the concept of epitaxy to 2D space, we developed and applied a new growth technique to hybrid isostructural but electrically dissimilar materials, such as the 2D epitaxial growth of hBN templated by graphene edge [1]. Scanning tunneling microscopy and spectroscopy measurements revealed a single-atomic-layer, in-plane heterostructure between graphene and hBN, as well as an abrupt 1D zigzag oriented boundary. In addition, the dI/dV conductance map unveiled the 1D interfacial states that are extended along, but localized at the boundary. We investigated spatial and energetic distributions of 1D boundary states. Also, low-energy electron microscopy and micro low-energy electron diffraction confirmed the heterostructure at mesoscopic scale and established that the graphene edge solely determines the crystallography of the hBN regardless of underlying the Cu(100) lattice. The Z-contrast scanning transmission electron microscopy further indicates an atomically sharp interface with a transition width of ~0.5 nm. We suggest that the graphene-hBN epitaxial heterostructure provides an excellent platform to explore heteroepitaxy in 2D space, and the unique functionalities at the 1D interface. [1] Lei Liu et al. Science343 163 (2014)