Soliton instability and fold formation in laterally compressed few-layer graphene

Abstract

We investigate -- through simulations and analytical calculations -- the consequences of uniaxial lateral compression applied to the upper layer of few-layer graphene. The simulations of compressed graphene show that strains larger than 2.8 \% induce soliton-like deformations that further develop into large, mobile folds. Such folds were indeed experimentally observed in graphene and other solid lubricants two-dimensional materials. Interestingly, in the soliton-fold regime the shear stress decreases with the strain s, initially as $s^{-2/3}$ and rapidly going to zero. Such instability is consistent with the recently observed negative dynamic compressibility of two-dimensional materials. We also predict that the curvatures of the soliton-folds are given by $r_c=\delta \sqrt{\beta /2\alpha },$ where $1\le \delta \le 2,$ and $\beta$ and $\alpha$ are respectively related to the layer bending modulus and to the exfoliation energy of the material. This finding might allow experimental estimates of the $\beta /\alpha$ ratio of two-dimensional materials from fold morphology.

References in corpus (7)

• The electronic properties of graphene
• The structure of suspended graphene sheets
• Periodically rippled graphene: growth and spatially resolved electronic structure
• Structure and electronic transport in graphene wrinkles
• Two Dimensional Ir-Cluster Lattices on Moiré of Graphene with Ir(111)
• Multiply Folded Graphene
• Gauge fields and interferometry in folded graphene

Cited by in corpus (1)

• Fast diffusion of water nanodroplets on graphene