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arXiv · 1911.10536

Large-scale critical behavior of the rippling phase transition for graphene membranes

Abstract

We analyze the spontaneous rippling of graphene membranes as function of the coupling between lattice deformations and electrons. We numerically study a model of an elastic membrane coupled to Dirac fermions. We identify a phase transition from a flat to a rippled configuration of the membrane when increasing the coupling and propose a scaling procedure that allows us to effectively reach arbitrary large system sizes. We find that the critical value of the coupling rapidly decays as the system increases its size, in agreement with the experimental observation of an unavoidable stable rippled state for suspended graphene membranes. This decay turns out to be controlled by a power law with a critical exponent $\sim 1/2$.

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Tommaso Cea, Miguel Ruiz-Garcia, Luis Bonilla, Francisco Guinea. 2019-11-26. Large-scale critical behavior of the rippling phase transition for graphene membranes. https://arxiv.org/abs/1911.10536

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