Abstract
We derive an effective two-dimensional Hamiltonian to describe the low-energy electronic excitations of a graphite bilayer, which correspond to chiral quasiparticles with a parabolic dispersion exhibiting Berry phase . Its high-magnetic-field Landau-level spectrum consists of almost equidistant groups of fourfold degenerate states at finite energy and eight zero-energy states. This can be translated into the Hall conductivity dependence on carrier density, , which exhibits plateaus at integer values of and has a double step between the hole and electron gases across zero density, in contrast to sequencing in a monolayer.
- Received 10 October 2005
DOI:https://doi.org/10.1103/PhysRevLett.96.086805
©2006 American Physical Society