“School of Physic”

Back to Papers Home
Back to Papers of School of Physic

Paper   IPM / Physic / 11349
School of Physics
  Title:   Observation of Plasmarons in Quasi-Free-Standing Doped Graphene
  Author(s): 
1.  A. Bostwick
2.  F. Speck
3.  T . Seyller
4.  K. Horn
5.  M. Polini
6.  R. Asgari
7.  A.H. MacDonald,
8.  E. Rotenberg
  Status:   Published
  Journal: Science
  No.:  5981
  Vol.:  328
  Year:  2010
  Pages:   999-1002
  Supported by:  IPM
  Abstract:
A hallmark of graphene is its unusual conical band structure that leads to a zero-energy band gap at a single Dirac crossing point. By measuring the spectral function of charge carriers in quasi-free-standing graphene with angle-resolved photoemission spectroscopy, we show that at finite doping the well-known linear Dirac spectrum does not provide a full description of the charge-carrying excitations. We observe composite ?plasmaron? particles, which are bound states of charge carriers with plasmons, the density oscillations of the graphene electron gas. The Dirac crossing point is resolved into three crossings: the first between pure charge bands, the second between pure plasmaron bands, and the third a ring-shaped crossing between charge and plasmaron bands.

Download TeX format
back to top
scroll left or right