Landau Level Spectroscopy of Ultrathin Graphite Layers
Landau Level Spectroscopy of Ultrathin Graphite Layers
Far infrared transmission experiments are performed on ultrathin epitaxial graphite samples in a magnetic field. The observed cyclotron resonance-like 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 x 10(6) m/s.