Morgado TA, Silveirinha MG. Negative Landau Damping in Bilayer Graphene.
PHYSICAL REVIEW LETTERS 2017;
119:133901. [PMID:
29341703 DOI:
10.1103/physrevlett.119.133901]
[Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Indexed: 06/07/2023]
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 direct current. This effect is triggered by electrons drifting through one of the graphene sheets and leads to wave instabilities and a spontaneous light emission (spasing) in the midinfrared 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 a 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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