title: Strong charge-transfer excitonic effects and the Bose-Einstein exciton condensate in graphane.
abstract: Using first principles many-body theory methods (GW+Bethe-Salpeter equation) we demonstrate that the optical properties of graphane are dominated by localized charge-transfer excitations governed by enhanced electron correlations in a two-dimensional dielectric medium. Strong electron-hole interaction leads to the appearance of small radius bound excitons with spatially separated electron and hole, which are localized out of plane and in plane, respectively. The presence of such bound excitons opens the path towards an excitonic Bose-Einstein condensate in graphane that can be observed experimentally.
authors.affiliation: Nano-Bio Spectroscopy group, Dpto. Física de Materiales, Universidad del País Vasco, Centro de Física de Materiales CSIC-UPV/EHU-MPC and DIPC, Av. Tolosa 72, E-20018 San Sebastián, Spain.
authors.forename: Pierluigi
authors.initials: P
authors.lastname: Cudazzo
authors.forename: Claudio
authors.initials: C
authors.lastname: Attaccalite
authors.forename: Ilya V
authors.initials: IV
authors.lastname: Tokatly
authors.forename: Angel
authors.initials: A
authors.lastname: Rubio
mesh_terms: D004579:Electron Transport; D004583:Electrons; D006108:Graphite / Q000737:chemistry*; D006865:Hydrogenation; D008958:Models, Molecular; D008968:Molecular Conformation; D011789:Quantum Theory
chemical_list: D006108:Graphite