Directional roll-up of nanomembranes mediated by wrinkling.
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 relaxation using a finite element method.
Institute for Integrative Nanosciences, IFW Dresden, Helmholtz Strasse 20, 01069 Dresden, Germany. p.cendula@ifw-dresden.de
Peter
P
Cendula
Suwit
S
Kiravittaya
Ingolf
I
Mönch
Joachim
J
Schumann
Oliver G
OG
Schmidt