arXiv 0804.21922008-04-14cond-mat.mes-hallcond-mat.mtrl-sci

Spectroscopic Signatures of Massless Gap Opening in Graphene

L. Benfatto, E. Cappelluti

发表信息：: Phys. Rev. B 78, 115434 (2008).
DOI：: 10.1103/PhysRevB.78.115434

英文摘要：

Gap opening in graphene is usually discussed in terms of a semiconducting-like spectrum, where the appearance of a finite gap at the Dirac point is accompanied by a finite mass for the fermions. In this Letter we propose a gap scenario from graphene which preserves the massless characters of the carriers. This approach explains recent spectroscopic measurements carried out in epitaxially-grown graphene, ranging from photoemission to optical transmission.

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