Light-driven liquid crystal elastomer kirigami: fluttering with splay and topology

Via finite element simulations, we model the actuation response of liquid crystal elastomer kirigami imprinted with topological microstructures. Microstructures include in-plane defects with a preset topological charge coexisting with director splay along sample thickness. In the spirit of kirigami (the japanese art of cutting paper), we investigate samples custom-cut to specific geometries and their corresponding out-of-plane actuation driven by light. We demostrate the actuation of a variety of samples, including the fluttering of a bio-mimetic elastomer butterfly. Our numerical studies are in remarkable agreement with experimental results and demostrate a fascinating actuation behavior arising from the interplay between microstructural topology, macroscopic geometry and stimulus-response.