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arXiv · 1405.5799

Breaking of symmetry in graphene growth on metal substrates

Vasilii I. Artyukhov·Yufeng Hao·Rodney S. Ruoff·Boris I. Yakobson
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Abstract

In graphene growth, island symmetry can become lower than the intrinsic symmetries of both graphene and the substrate. First-principles calculations and Monte Carlo modeling explain the shapes observed in our experiments and earlier studies for various metal surface symmetries. For equilibrium shape, edge energy variations $δE$ manifest in distorted hexagons with different ground-state edge structures. In growth or nucleation, energy variation enters exponentially as $\sim e^{δE / k_{B} T}$, strongly amplifying the symmetry breaking, up to completely changing the shapes to triangular, ribbon-like, or rhombic.

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Vasilii I. Artyukhov, Yufeng Hao, Rodney S. Ruoff, Boris I. Yakobson. 2015-03-12. Breaking of symmetry in graphene growth on metal substrates. https://doi.org/10.1103/physrevlett.114.115502

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