Title
Diffraction paradox: An unusually broad diffraction background marks high quality graphene
Publication Date
10-15-2019
Department
Ames Laboratory; Chemistry; Materials Science and Engineering; Physics and Astronomy
Campus Units
Ames Laboratory, Chemistry, Materials Science and Engineering, Physics and Astronomy
OSTI ID+
1574018
Report Number
IS-J 10074
DOI
10.1103/PhysRevB.100.155307
Journal Title
Physical Review B
Volume Number
100
Issue Number
15
First Page
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.
DOE Contract Number(s)
AC02-07CH11358; SFB1242
Language
en
Department of Energy Subject Categories
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY
Publisher
Iowa State University Digital Repository, Ames IA (United States)
