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arXiv · 1001.2762

Coulomb screening and collective excitations in biased bilayer graphene

Xue-Feng Wang·Tapash Chakraborty
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Abstract

We have investigated the Coulomb screening properties and plasmon spectrum in a bilayer graphene under a perpendicular electric bias. The bias voltage applied between the two graphene layers opens a gap in the single particle energy spectrum and modifies the many-body correlations and collective excitations. The energy gap can soften the plasmon modes and lead to a crossover of the plasmons from a Landau damped mode to being undamped. Plasmon modes of long lifetime may be observable in experiments and may have potentials for device applications.

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Xue-Feng Wang, Tapash Chakraborty. 2010-01-15. Coulomb screening and collective excitations in biased bilayer graphene. https://doi.org/10.1103/physrevb.81.081402

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