When pursuing a degree in fine arts 15 years ago, Matthew Shlian never dreamed that he would one day be the coauthor of scientific research papers on nanoengineering and solar power (1, 2). But, the Ann Arbor-based artist and designer was exactly that earlier this year. A collaboration between Shlian and engineering colleagues at the University of Michigan is now coming to fruition in the form of technology inspired by the paper-cutting art known as kirigami. The Michigan work exemplifies how some cutting edge technology research has been shaped by the ancient craft.

Matthew Shlian incorporates elements of kirigami into his science research collaborations as well as his paper sculptures, such as this one. Image courtesy of Matthew Shlian (mattshlian.com).

In essence, kirigami is a variant of origami, the art of paper folding. The words derive from the Japanese for cutting (kiru), folding (oru), and paper (kami). Folding and cutting of paper to create ceremonial or decorative objects dates back centuries in Asia and Europe. The modern notion of origami as an art and recreational craft (and eschewing all cuts in its purest form) took shape last century.

Standard origami starts with a pristine sheet of paper, most often square, and proceeds solely by adding folds: no cutting or gluing is allowed. In contrast, kirigami, relies on both cutting and folding. Designs range from flat symmetrical cut-out decorations like schoolroom snowflakes to elaborate patterns that form 3D models similar to book pop-ups. (Early in his paper-sculpting career, Shlian worked on pop-up books, among other pursuits.)

Making the Cut Why has this low-tech art form found a home in science and technology pursuits? One attraction is the ability to turn 2D materials into 3D structures solely by introducing cuts and folds. For example, John A. Rogers of the University of Illinois at Urbana–Champaign and collaborators have shown how membranes can be designed to form predictable 3D structures ranging from the nanoscale to the mesoscale (3). The group used lithographic techniques to build membranes of silicon, metal, and polymer (in various combinations), with specific geometries and patterns of cuts. Each flat unit is anchored at a number of points to a stretched elastomer substrate. When the tension is relaxed, the substrate contracts, dragging these anchor points closer together, like a person pushing together corners of a paper sheet; the precut membranes buckle out of the plane. The kirigami cuts help determine the final 3D shapes and alleviate stresses that could otherwise cause the material to fracture. Researchers are interested in such 3D structures for uses such as optoelectronics and nanostructured biomedical devices. Solar cells, such as these made from thin-film crystalline gallium arsenide, were designed with kirigami cutting techniques. Adapted from ref. 2. Kirigami structures also confer elasticity. For example, Hanqing Jiang of Arizona State University and his coworkers developed lithium-ion batteries that are cut and folded into a flexible chain, which can be worn as an elastic armband to power wearable technology (4). Kirigami can make a sheet of paper stretchable, like a spring, just by adding parallel cuts, dividing it into an array of thin strips with short cross connections. When the paper is pulled perpendicular to the cuts, they open up and allow the sheet to stretch, while the strips buckle into a tilted wavy arrangement. At longer extensions, the result looks more like a fishnet than a sheet of paper. Paul McEuen, Melina Blees, and colleagues at Cornell University built a version of this springy structure out of graphene, the single-atom-thick sheets of carbon that nanotechnologists are studying for a plethora of applications (5). McEuen’s group also measured the bending stiffness of micrometer-sized graphene sheets and obtained values that show graphene is as suitable for kirigami as standard paper.