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arXiv · 1703.03623

Negative Landau damping in bilayer graphene

Tiago A. Morgado·Mário G. Silveirinha
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Abstract

We theoretically demonstrate that a system formed by two coupled graphene sheets enables a negative damping regime wherein graphene plasmons are pumped by a DC current. This effect is triggered by electrons drifting through one of the graphene sheets and leads to the spontaneous light emission (spasing) and wave instabilities in the mid-infrared range. It is shown that there is a deep link between the drift-induced instabilities and wave instabilities in moving media, as both result from the hybridization of oscillators with oppositely signed frequencies. With a thickness of few nanometers and wide spectral tunability, the proposed structure may find interesting applications in nanophotonic circuitry as an on-chip light source.

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Tiago A. Morgado, Mário G. Silveirinha. 2017-03-10. Negative Landau damping in bilayer graphene. https://doi.org/10.1103/physrevlett.119.133901

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