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Laser-induced surface relief nanocrowns as a manifestation of nanoscale Rayleigh-Plateau hydrodynamic instability

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 نشر من قبل Alexander Kuchmizhak
 تاريخ النشر 2019
  مجال البحث فيزياء
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Nanoscale hydrodynamic instability of ring-like molten rims around ablative microholes produced in nanometer-thick gold films by tightly focused nanosecond-laser pulses was experimentally explored in terms of laser pulse energy and film thickness. These parametric dependencies of basic instability characteristics - order and period of the resulting nanocrowns - were analyzed, revealing its apparently Rayleigh-Plateau character, as compared to much less consistent possible van der Waals and impact origins. Along with fundamental importance, these findings will put forward pulsed laser ablation as an alternative facile inexpensive table-top approach to study such hydrodynamic instabilities developing at nanosecond temporal and nanometer spatial scales.



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