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arXiv · 0905.2883

Dynamical response functions and collective modes of bilayer graphene

Giovanni Borghi·Marco Polini·Reza Asgari·A. H. MacDonald
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Abstract

Bilayer graphene (BLG) has recently attracted a great deal of attention because of its electrically tunable energy gaps and its unusual electronic structure. In this Letter we present analytical and semi-analytical expressions, based on the four-band continuum model, for the layer-sum and layer-difference density response functions of neutral and doped BLG. These results demonstrate that BLG density-fluctuations can exhibit either single-component massive-chiral character or standard two-layer character, depending on energy and doping.

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Giovanni Borghi, Marco Polini, Reza Asgari, A. H. MacDonald. 2009-05-18. Dynamical response functions and collective modes of bilayer graphene. https://doi.org/10.1103/physrevb.80.241402

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