title: Chaotic Dirac billiard in graphene quantum dots.
abstract: The exceptional electronic properties of graphene, with its charge carriers mimicking relativistic quantum particles and its formidable potential in various applications, have ensured a rapid growth of interest in this new material. We report on electron transport in quantum dot devices carved entirely from graphene. At large sizes (>100 nanometers), they behave as conventional single-electron transistors, exhibiting periodic Coulomb blockade peaks. For quantum dots smaller than 100 nanometers, the peaks become strongly nonperiodic, indicating a major contribution of quantum confinement. Random peak spacing and its statistics are well described by the theory of chaotic neutrino billiards. Short constrictions of only a few nanometers in width remain conductive and reveal a confinement gap of up to 0.5 electron volt, demonstrating the possibility of molecular-scale electronics based on graphene.
authors.affiliation: Manchester Centre for Mesoscience and Nanotechnology, University of Manchester, Manchester M13 9PL, UK.
authors.forename: L A
authors.initials: LA
authors.lastname: Ponomarenko
authors.forename: F
authors.initials: F
authors.lastname: Schedin
authors.forename: M I
authors.initials: MI
authors.lastname: Katsnelson
authors.forename: R
authors.initials: R
authors.lastname: Yang
authors.forename: E W
authors.initials: EW
authors.lastname: Hill
authors.forename: K S
authors.initials: KS
authors.lastname: Novoselov
authors.forename: A K
authors.initials: AK
authors.lastname: Geim