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arXiv · 1207.5675

Strain and rotation fields of dislocations in graphene

Abstract

Strain and rotation fields of dislocations in monolayer graphene have been mapped in a recent experiment. These fields are finite everywhere and differ from those given by linear elasticity which does not consider rotation explicitly and predicts infinite rotation and strains at the dislocation point. A derivative regularization of two-dimensional linear elasticity fixes these shortcomings. The theory adds rotation, dislocation and residual strain energies to the usual elastic energy. There are two extra material constants that determine the size of the dislocation core and are determined from experimental data. These findings are useful for studies of dislocations in graphene and for analyzing incipient plasticity in two dimensional crystals.

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L. L. Bonilla, A. Carpio. 2012-07-24. Strain and rotation fields of dislocations in graphene. https://arxiv.org/abs/1207.5675

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