Directional roll-up of nanomembranes mediated by wrinkling
| P. Cendula, S. Kiravittaya, I. Mönch, J. Schumann, O. G. Schmidt Nano Lett. 11, 236 (2011) URL PDF |
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| Abstract | |
| We investigate the relaxation of rectangular wrinkled thin films intrinsically containing an initial strain gradient. A preferential rolling direction, depending on wrinkle geometry and strain gradient, is theoretically predicted and experimentally verified. In contrast to typical rolled-up nanomembranes, which bend perpendicular to the longer edge of rectangular patterns, we find a regime where rolling parallel to the longer edge of the wrinkled film is favorable. A nonuniform radius of the rolled-up film is well reproduced by elasticity theory and simulations of the film elaxation using a finite element method. |