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arXiv · 1405.7607

Strong coupling in the far-infrared between graphene plasmons and the surface optical phonons of silicon dioxide

Isaac. J. Luxmoore·Choon How Gan·Peter Q. Liu·Federico Valmorra·Penglei Li·Jerome Faist·Geoffrey R. Nash
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Abstract

We study plasmonic resonances in electrostatically gated graphene nanoribbons on silicon dioxide substrates. Absorption spectra are measured in the mid-far infrared and reveal multiple peaks, with width-dependent resonant frequencies. We calculate the dielectric function within the random phase approximation and show that the observed spectra can be explained by surface-plasmon-phonon-polariton modes, which arise from coupling of the graphene plasmon to three surface optical phonon modes in the silicon dioxide.

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Isaac. J. Luxmoore, Choon How Gan, Peter Q. Liu, Federico Valmorra, Penglei Li, Jerome Faist, Geoffrey R. Nash. 2014-05-29. Strong coupling in the far-infrared between graphene plasmons and the surface optical phonons of silicon dioxide. https://doi.org/10.1021/ph500233s

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