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arXiv · 0709.1230

Exciton formation in graphene bilayer

Raoul Dillenschneider·Jung Hoon Han
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Abstract

Exciton instability in graphene bilayer systems is studied in the case of a short-ranged Coulomb interaction and a finite voltage difference between the layers. Self-consistent exciton gap equations are derived and solved numerically and analytically under controlled approximation. We obtain that a critical strength of the Coulomb interaction exists for the formation of excitons. The critical strength depends on the amount of voltage difference between the layers and on the inter-layer hopping parameter.

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Raoul Dillenschneider, Jung Hoon Han. 2008-03-04. Exciton formation in graphene bilayer. https://doi.org/10.1103/physrevb.78.045401

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