Spatially resolved one-dimensional boundary states in graphene–hexagonal boron nitride planar heterostructures

Jewook Park (1) , Jaekwang Lee (2, 1) , Lei Liu (3) , Kendal Clark (4) , Corentin Durand (5) , Changwon Park (1) , Bobby Sumpter (1) , Arthur Baddorf (1) , Ali Mohsin (3) , Mina Yoon (1) , Gong Gu (3) , An-Ping Li (1)

1 CNMS - Center for Nanophase Materials Sciences [Oak Ridge]
2 Smart Game Research Team, Contents Research Division
3 The University of Tennessee [Knoxville]
4 CMU- Central Methodist University, - Central Methodist University
5 CEMES - Centre d'élaboration de matériaux et d'études structurales

Two-dimensional interfaces between crystalline materials have been shown to generate unusual interfacial electronic states in complex oxides. Recently, a one-dimensional interface has been realized in hexagonal boron nitride and graphene planar heterostructures, where a polar-on-nonpolar one-dimensional boundary is expected to possess peculiar electronic states associated with edge states of graphene and the polarity of boron nitride. Here we present a combined scanning tunnelling microscopy and first-principles theory study of the graphene–boron nitride boundary to provide a first glimpse into the spatial and energetic distributions of the one-dimensional boundary states down to atomic resolution. The revealed boundary states are about 0.6 eV below or above the Fermi level depending on the termination of the boron nitride at the boundary, and are extended along but localized at the boundary. These results suggest that unconventional physical effects similar to those observed at two-dimensional interfaces can also exist in lower dimensions.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Jewook Park, Jaekwang Lee, Lei Liu, Kendal Clark, Corentin Durand, et al.. Spatially resolved one-dimensional boundary states in graphene–hexagonal boron nitride planar heterostructures. Nature Communications, 2014, 5 (1), pp.5403. ⟨10.1038/ncomms6403⟩. ⟨hal-01923494⟩