Coherent phases and magnetoexcitons in graphene



Unique band structure peculiarities of graphene imply that near Fermi level electrons are described by two-dimensional Dirac equation for massless particles. We investigate how these peculiarities manifest in electron–hole pairing and properties of indirect magnetoexcitons in two spatially separated, independently gated graphene layers. For electron–hole pairing, we derive asymptotical expressions for the gap in energy spectrum and discuss system behavior at various controlling parameters. We derive dispersion relations for magnetoexcitons and their effective-mass decompositions, and also discuss a possibility of magnetoexcitonic superfluidity. The systems under consideration can reveal coherent properties, dissipationless currents and Josephson phenomena at room temperature. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)