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arXiv · 1502.00535

Localized Surface Plasmons in Vibrating Graphene Nanodisks

Abstract

Localized surface plasmons are confined collective oscillations of electrons in metallic nanoparticles. When driven by light, the optical response is dictated by geometrical parameters and the dielectric environment and plasmons are therefore extremely important for sensing applications. Plasmons in graphene disks have the additional benefit to be highly tunable via electrical stimulation. Mechanical vibrations create structural deformations in ways where the excitation of localized surface plasmons can be strongly modulated. We show that the spectral shift in such a scenario is determined by a complex interplay between the symmetry and shape of the modal vibrations and the plasmonic mode pattern. Tuning confined modes of light in graphene via acoustic excitations, paves new avenues in shaping the sensitivity of plasmonic detectors, and in the enhancement of the interaction with optical emitters, such as molecules, for future nanophotonic devices.

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Weihua Wang, Bo-Hong Li, Erik Stassen, N. Asger Mortensen, Johan Christensen. 2016-01-14. Localized Surface Plasmons in Vibrating Graphene Nanodisks. https://doi.org/10.1039/c5nr08812g

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