Shape Memory Assemblies of Janus Ellipsoids

A goal in colloidal self-assembly is to create self-assembled structures capable of mimicking the functionality of micron-scale structures found in nature, which can be actuated to control optical, transport, and mechanical properties. We report a joint computational and experimental study in which we draw inspiration from the structure of myofibrils to create shape-memory colloidal assemblies that can be similarly actuated. We use Janus ellipsoids as building blocks to assemble self-limiting one-dimensional fibers. The unit cell of this ordered assembly can rapidly and reversibly reconfigure via a sliding mechanism upon application of an alternating current electric field.