Impurity scattering and size quantization effects in a single graphene nanoflake
Journal article, 2017

By using Fourier-transform scanning tunneling spectroscopy we measure the interference patterns produced by the impurity scattering of confined Dirac quasiparticles in epitaxial graphene nanoflakes. Upon comparison of the experimental results with tight-binding calculations of realistic model flakes, we show that the characteristic features observed in the Fourier-transformed local density of states are related to scattering between different transverse modes (subbands) of a graphene nanoflake and allow direct insight into the gapped electronic spectrum of graphene. We also observe a strong reduction of quasiparticle lifetime which is attributed to the interaction with the underlying substrate. In addition, we show that the distribution of the on-site energies at flower defects leads to an effectively broken pseudospin selection rule, where intravalley backscattering is allowed.

state

transport

Physics

films

fabrication

epitaxial graphene

nanoribbons

ag(111)

electronic-properties

Author

J. Tesch

University of Konstanz

P. Leicht

University of Konstanz

F. Blumenschein

University of Konstanz

L. Gragnaniello

University of Konstanz

Anders Bergvall

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

Tomas Löfwander

Chalmers, Microtechnology and Nanoscience (MC2), Applied Quantum Physics

M. Fonin

University of Konstanz

Physical Review B

24699950 (ISSN) 24699969 (eISSN)

Vol. 95 7 075429

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Subject Categories

Nano Technology

Condensed Matter Physics

DOI

10.1103/PhysRevB.95.075429

More information

Created

10/8/2017