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Evidence for contact delocalization in atomic scale friction

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 نشر من قبل Sergey Krylov
 تاريخ النشر 2007
  مجال البحث فيزياء
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We analyze an advanced two-spring model with an ultra-low effective tip mass to predict nontrivial and physically rich fine structure in the atomic stick-slip motion in Friction Force Microscopy (FFM) experiments. We demonstrate that this fine structure is present in recent, puzzling experiments. This shows that the tip apex can be completely or partially delocalized, thus shedding new light on what is measured in FFM and, possibly, what can happen with the asperities that establish the contact between macroscopic sliding bodies.



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