title: Quantum-confined electronic states in atomically well-defined graphene nanostructures.
abstract: Despite the enormous interest in the properties of graphene and the potential of graphene nanostructures in electronic applications, the study of quantum-confined states in atomically well-defined graphene nanostructures remains an experimental challenge. Here, we study graphene quantum dots (GQDs) with well-defined edges in the zigzag direction, grown by chemical vapor deposition on an Ir(111) substrate by low-temperature scanning tunneling microscopy and spectroscopy. We measure the atomic structure and local density of states of individual GQDs as a function of their size and shape in the range from a couple of nanometers up to ca. 20 nm. The results can be quantitatively modeled by a relativistic wave equation and atomistic tight-binding calculations. The observed states are analogous to the solutions of the textbook "particle-in-a-box" problem applied to relativistic massless fermions.
authors.affiliation: Department of Applied Physics, Aalto University School of Science, 00076 Aalto, Finland.
authors.forename: Sampsa K
authors.initials: SK
authors.lastname: Hämäläinen
authors.forename: Zhixiang
authors.initials: Z
authors.lastname: Sun
authors.forename: Mark P
authors.initials: MP
authors.lastname: Boneschanscher
authors.forename: Andreas
authors.initials: A
authors.lastname: Uppstu
authors.forename: Mari
authors.initials: M
authors.lastname: Ijäs
authors.forename: Ari
authors.initials: A
authors.lastname: Harju
authors.forename: Daniël
authors.initials: D
authors.lastname: Vanmaekelbergh
authors.forename: Peter
authors.initials: P
authors.lastname: Liljeroth