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Superlubric to stick-slip sliding of incommensurate graphene flakes on graphite

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 نشر من قبل Annalisa Fasolino
 تاريخ النشر 2015
  مجال البحث فيزياء
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We calculate the friction of fully mobile graphene flakes sliding on graphite. For incommensurately stacked flakes, we find a sudden and reversible increase in friction with load, in agreement with experimental observations. The transition from smooth sliding to stick-slip and the corresponding increase in friction is neither due to rotations to commensurate contact nor to dislocations but to a pinning caused by vertical distortions of edge atoms also when they are saturated by Hydrogen. This behavior should apply to all layered materials with strong in-plane bonding.



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