arXiv 0902.12302009-02-07cond-mat.str-elcond-mat.mes-hall

Fermi Velocity Enhancement in Monolayer and Bilayer Graphene

Giovanni Borghi, Marco Polini, Reza Asgari, A. H. MacDonald

备注：: 8 pages, 5 figures, submitted to the proceedings of the ICTP Conference `Graphene Week 2008' (Trieste, Italy)
发表信息：: Solid State Commun. 149, 1117 (2009)
DOI：: 10.1016/j.ssc.2009.02.053

英文摘要：

In single-layer graphene sheets non-local interband exchange leads to a renormalized Fermi-surface effective mass which vanishes in the low carrier-density limit. We report on a comparative study of Fermi surface effective mass renormalization in single-layer and AB-stacked bilayer graphene. We explain why the mass does not approach zero in the bilayer case, although its value is still strongly suppressed.

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