Low-Temperature Friction of Suspended Graphene: Negative friction?

Zhao Wang

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arXiv · 1910.00804

Low-Temperature Friction of Suspended Graphene: Negative friction?

Zhao Wang

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Abstract

Using molecular dynamics simulations, we probe a suspended graphene layer by a diamond-like-carbon tip at various temperatures. The force acting on the tip in the sliding direction is measured to be negative at liquid-helium temperature. This negative force is found to be associated with a spontaneous lateral oscillation of the suspended graphene in favor of a low interface potential corrugation. Our hypothesis is that, at low temperature, this oscillation induces an important hidden contribution to the friction force in the lateral direction. This functions as a particular energy dissipation mechanism at nanoscale.

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Zhao Wang. 2019-10-02. Low-Temperature Friction of Suspended Graphene: Negative friction?. https://arxiv.org/abs/1910.00804

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