Electric-field-and contact-force-induced tunable patterns in slipping soft elastic films

Abstract

We show that the introduction of slippage has a profound effect on instabilities induced by electric field or contact forces in soft solid elastic films. The critical force required to initiate these instabilities is markedly reduced because of slippage, and is lowest when the slippage arises from an intercalating viscous layer between the elastic film and its rigid substrate. Remarkably, unlike in rigidly bonded elastic films, the length scale of instabilities can be tuned by changing the film thicknesses, material properties of the films, and the strength of the destabilizing force of the bilayers. This feature can be potentially exploited in meso-patterning applications.