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Role of Thermal Fluctuations in Nonlinear Thin Film Dewetting

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 نشر من قبل Svetozar Nesic
 تاريخ النشر 2015
  مجال البحث فيزياء
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The spontaneous formation of droplets via dewetting of a thin fluid film from a solid substrate allows for materials nanostructuring, under appropriate experimental control. While thermal fluctuations are expected to play a role in this process, their relevance has remained poorly understood, particularly during the nonlinear stages of evolution. Within a stochastic lubrication framework, we show that thermal noise speeds up and substantially influences the formation and evolution of the droplet arrangement. As compared with their deterministic counterparts, for a fixed spatial domain, stochastic systems feature a smaller number of droplets, with a larger variability in sizes and space distribution. Finally, we discuss the influence of stochasticity on droplet coarsening for very long times.



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