title: Rippling graphene at the nanoscale through dislocation addition.
abstract: Ripples in graphene are an out-of-plane distortion that help stabilize suspended monolayer graphene. The introduction of disclinations and dislocations into the lattice of graphene is predicted to extensively ripple graphene to form "hillocks" to accommodate the strain in the system. Here, we confirm this theoretical prediction by intentionally introducing large numbers of dislocations into a predefined area of pristine monolayer graphene by scanning focused electron beam irradiation and imaging the rippled atomic lattice structure with aberration-corrected transmission electron microscopy. Hillocks are observed and analyzed using geometric phase analysis to determine heights of ~0.5 nm. Time-dependent imaging shows the rippling is dynamic under the electron beam and can fluctuate between different structural configurations. This demonstrates a means of perturbing the structure of graphene in all three spatial dimensions with nanoscale precision.
authors.affiliation: Department of Materials, University of Oxford , Parks Rd, Oxford, OX1 3PH, United Kingdom.
authors.forename: Jamie H
authors.initials: JH
authors.lastname: Warner
authors.forename: Ye
authors.initials: Y
authors.lastname: Fan
authors.forename: Alex W
authors.initials: AW
authors.lastname: Robertson
authors.forename: Kuang
authors.initials: K
authors.lastname: He
authors.forename: Euijoon
authors.initials: E
authors.lastname: Yoon
authors.forename: Gun Do
authors.initials: GD
authors.lastname: Lee
mesh_terms: D006108:Graphite / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties
chemical_list: D006108:Graphite