Magneto electronic properties of a graphite sheet

Magnetoelectronic structures of a two-dimensional (2D) graphite sheet are calculated by the tight-binding model. They are very sensitive to the magnitude of perpendicular magnetic field (B). B imposes the periodical boundary condition on the Bloch functions in the real and momentum spaces. Thus, B changes energy dispersions, energy spacing, bandwidth, and oscillation period of Landau levels. B could reduce the dimensionality of a graphite sheet. Energy dispersions mainly exhibit zero-dimensional (or 1 D) characteristics. A lot of delta-function-like peaks (or square-root peaks) in the density of states can be clearly found. The magnetic field dramatically changes the joint density of states and the magnetoabsorption spectra. So, many peaks with different structures are produced. (C) 2004 Elsevier Ltd. All rights reserved.