Landau level spectroscopy of ultrathin graphite layers

Abstract

Far infrared transmission experiments are performed on ultrathin epitaxial graphite samples in a magnetic field. The observed cyclotron resonancelike and electron-positron-like transitions are in excellent agreement with the expectations of a single-particle model of Dirac fermions in graphene, with an effective velocity of c =1.03×106m/s. © 2006 The American Physical Society.