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arXiv · 1311.4690

Multiple Excitation of Confined Graphene Plasmons by Single Free Electrons

F. Javier Garcia de Abajo
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Abstract

We show that free electrons can efficiently excite plasmons in doped graphene with probabilities of order one per electron. More precisely, we predict multiple excitations of a single confined plasmon mode in graphene nanostructures. These unprecedentedly large electron-plasmon couplings are explained using a simple scaling law and further investigated through a general quantum description of the electron-plasmon interaction. From a fundamental viewpoint, multiple plasmon excitations by a single electron provides a unique tool for exploring the bosonic quantum nature of these collective modes. Our study does not only open a viable path towards multiple excitation of a single plasmon mode by single electrons, but it also reveals graphene nanostructures as ideal systems for producing, detecting, and manipulating plasmons using electron probes.

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F. Javier Garcia de Abajo. 2013-11-19. Multiple Excitation of Confined Graphene Plasmons by Single Free Electrons. https://doi.org/10.1021/nn405476t

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