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arXiv · 0906.0479

Electric field Induced Patterns in Soft Visco-elastic films: From Long Waves of Viscous Liquids to Short Waves of Elastic Solids

N. Arun·Ashutosh Sharma·Partho S. G. Pattader·Indrani Banerjee·Hemant M. Dixit·K. S. Narayan
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Abstract

We show that the electric field driven surface instability of visco-elastic films has two distinct regimes: (1) The visco-elastic films behaving like a liquid display long wavelengths governed by applied voltage and surface tension, independent of its elastic storage and viscous loss moduli, and (2) the films behaving like a solid require a threshold voltage for the instability whose wavelength always scales as ~ 4 x film thickness, independent of its surface tension, applied voltage, loss and storage moduli. Wavelength in a narrow transition zone between these regimes depends on the storage modulus.

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N. Arun, Ashutosh Sharma, Partho S. G. Pattader, Indrani Banerjee, Hemant M. Dixit, K. S. Narayan. 2009-06-02. Electric field Induced Patterns in Soft Visco-elastic films: From Long Waves of Viscous Liquids to Short Waves of Elastic Solids. https://doi.org/10.1103/physrevlett.102.254502

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