Campus Units

Chemistry, Materials Science and Engineering, Physics and Astronomy, Ames Laboratory

Document Type

Article

Publication Version

Published Version

Publication Date

10-15-2019

Journal or Book Title

Physical Review B

Volume

100

Issue

15

First Page

155307

DOI

10.1103/PhysRevB.100.155307

Abstract

The realization of the unusual properties of two-dimensional (2D) materials requires the formation of large domains of single-layer thickness, extending over the mesoscale. It is found that the formation of uniform graphene on SiC, contrary to textbook diffraction, is signaled by a strong bell-shaped component (BSC) around the (00) and G(10) spots (but not around the substrate spots). The BCS is also seen on graphene grown on metals, because a single uniform graphene layer can be also grown with large lateral size. It is only seen by electron diffraction but not with x-ray or He scattering. Although the origin of such an intriguing result is unclear, its presence in the earlier literature (but never mentioned) points to its robustness and significance. A likely mechanism relates to the the spatial confinement of the graphene electrons, within a single layer. This leads to large spread in their wave vector which is transferred by electron-electron interactions to the elastically scattered electrons to generate the BSC.

Comments

This article is published as Chen, S., M. Horn von Hoegen, P. A. Thiel, and M. C. Tringides. "Diffraction paradox: An unusually broad diffraction background marks high quality graphene." Physical Review B 100, no. 15 (2019): 155307. DOI: 10.1103/PhysRevB.100.155307. Posted with permission.

Copyright Owner

American Physical Society

Language

en

File Format

application/pdf

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