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arXiv · 1703.00051

Strong thermal and electrostatic manipulation of the Casimir force in graphene multilayers

Abstract

We show that graphene-dielectric multilayers give rise to an unusual tunability of the Casimir-Lifshitz forces, and allow to easily realize completely different regimes within the same structure. Concerning thermal effects, graphene-dielectric multilayers take advantage from the anomalous features predicted for isolated suspended graphene sheets, even though they are considerably affected by the presence of the dielectric substrate. They can also archive the anomalous non-monotonic thermal metallic behavior by increasing the graphene sheets density and their Fermi energy. In addition to a strong thermal modulation occurring at short separations, in a region where the force is orders of magnitude larger than the one occurring at large distances, the force can be also adjusted by varying the number of graphene layers as well as their Fermi energy levels, allowing for relevant force amplifications which can be tuned, very rapidly and in-situ, by simply applying an electric potential. Our predictions can be relevant for both Casimir experiments and micro/nano electromechanical systems and in new devices for technological applications.

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Chahine Abbas, Brahim Guizal, Mauro Antezza. 2017-02-28. Strong thermal and electrostatic manipulation of the Casimir force in graphene multilayers. https://doi.org/10.1103/physrevlett.118.126101

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