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arXiv · 1906.04187

Discontinuous evolution of the structure of stretching polycrystalline graphene

Federico D'Ambrosio·Vladimir Juričić·Gerard T. Barkema
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Abstract

Polycrystalline graphene has an inherent tendency to buckle, i.e. develop out-of-plane, three-dimensional structure. A force applied to stretch a piece of polycrystalline graphene influences the out-of-plane structure. Even if the graphene is well-relaxed, this happens in non-linear fashion: occasionally, a tiny increase in stretching force induces a significant displacement, in close analogy to avalanches, which in turn can create vibrations in the surrounding medium. We establish this effect in computer simulations: by continuously changing the strain, we follow the displacements of the carbon atoms that turn out to exhibit a discontinuous evolution. Furthermore, the displacements exhibit a hysteretic behavior upon the change from low to high stress and back. These behaviors open up a new direction in studying dynamical elasticity of polycrystalline quasi-two-dimensional systems, and in particular the implications on their mechanical and thermal properties.

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Federico D'Ambrosio, Vladimir Juričić, Gerard T. Barkema. 2019-10-25. Discontinuous evolution of the structure of stretching polycrystalline graphene. https://doi.org/10.1103/physrevb.100.161402

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