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arXiv · 1811.00040

Interaction of surface acoustic waves with electronic excitations in graphene

A. Hernández-Mínguez·Y. -T. Liou·P. V. Santos
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Abstract

This article reviews the main theoretical and experimental advances regarding the interaction between surface acoustic waves (SAWs) and electronic excitations in graphene. The coupling of the graphene electron gas to the SAW piezoelectric field can modify the propagation properties of the SAW, and even amplify the intensity of SAWs traveling along the graphene layer. Conversely, the periodic electric and strain fields of the SAW can be used to modify the graphene Dirac cone and to couple light into graphene plasmons. Finally, SAWs can generate acousto-electric currents in graphene. These increase linearly with the SAW frequency and power but, in contrast to conventional currents, they depend non-monotonously on the graphene electric conductivity. Most of these functionalities have been reported in graphene transferred to the surface of strong piezoelectric insulators. The recent observation of acousto-electric currents in epitaxial graphene on SiC opens the way to the large-scale fabrication of graphene-based acousto-electric devices patterned directly on a semi-insulating wafer.

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A. Hernández-Mínguez, Y. -T. Liou, P. V. Santos. 2018-10-31. Interaction of surface acoustic waves with electronic excitations in graphene. https://doi.org/10.1088/1361-6463%2Faad593

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