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arXiv · 1610.06758

Graphene Plasmons in Triangular Wedges and Grooves

P. A. D. Gonçalves·E. J. C. Dias·Sanshui Xiao·M. I. Vasilevskiy·N. Asger Mortensen·N. M. R. Peres
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Abstract

The ability to effectively guide electromagnetic radiation below the diffraction limit is of the utmost importance in the prospect of all-optical plasmonic circuitry. Here, we propose an alternative solution to conventional metal-based plasmonics by exploiting the deep subwavelength confinement and tunability of graphene plasmons guided along the apex of a graphene-covered dielectric wedge or groove. In particular, we present a quasi-analytic model to describe the plasmonic eigenmodes in such a system, including the complete determination of their spectrum and corresponding induced potential and electric field distributions. We have found that the dispersion of wedge/groove graphene plasmons follows the same functional dependence as their flat-graphene plasmons counterparts, but now scaled by a (purely) geometric factor in which all the information about the system's geometry is contained. We believe our results pave the way for the development of novel custom-tailored photonic devices for subwavelength waveguiding and localization of light based on recently discovered 2D materials.

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P. A. D. Gonçalves, E. J. C. Dias, Sanshui Xiao, M. I. Vasilevskiy, N. Asger Mortensen, N. M. R. Peres. 2016-10-21. Graphene Plasmons in Triangular Wedges and Grooves. https://doi.org/10.1021/acsphotonics.6b00674

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