Figure 3: Electro-mechanical activation of EMCR elastomer films.

Schematic illustrations of (a) the experimental setup, (b) wrinkle initiation and (c) crater formation. The arrows in c indicate the locations of large deformation in the EMCR film. The fluorescence intensity of the EMCR film is first equilibrated to a force-free photostationary state by being exposed to green light for 3 min, and then activated with ramping electric field. (dI–VI) Optical microscope and (eI–VI) fluorescent microscope images of the EMCR film under varied electric fields. Image VI of e is the EMCR film illuminated by the green light for 3 min. The thicknesses of EMCR elastomer, buffer elastomer and protective insulator are ~21, ~106 and 125 μm, respectively. The applied voltages through (dI–dV) are 0, 3, 10, 12 and 14 kV, respectively. The scale bars in d and e denote 250 μm. (fI–V) Finite-element calculations of the first invariant in the EMCR film under increasing electric field.