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arXiv · 1003.1167

Strong charge-transfer excitonic effects and Bose-Einstein exciton-condensate in graphane

Pierluigi Cudazzo·Claudio Attacalite·Ilya V. Tokatly·Angel Rubio
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Abstract

Using first principles many-body theory methods (GW+BSE) we demonstrate that 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 on excitonic Bose-Einstein condensate in graphane that can be observed experimentally.

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Pierluigi Cudazzo, Claudio Attacalite, Ilya V. Tokatly, Angel Rubio. 2010-03-05. Strong charge-transfer excitonic effects and Bose-Einstein exciton-condensate in graphane. https://doi.org/10.1103/physrevlett.104.226804

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