Bouncing of a droplet on a superhydrophobic surface in AC electrowetting

We introduce a droplet-jumping phenomenon on a superhydrophobic surface driven by the resonant AC electrowetting. The resonant electrical actuation enables a droplet to accumulate sufficient surface energy for jumping, and superhydrophobic surface minimizes adhesion and hysteresis effects. They provide the effective energy conversion from the surface energy to the kinetic energy and improve the stability and the reproducibility of the droplet jumping. The controlled droplet jumping made by the resonant AC electrowetting could place another milestone in digital microfluidics by establishing a potential way to realize the three-dimensional droplet manipulation based on the conventional single plate EWOD configurations. This abstract is related to a fluid dynamics video for the gallery of fluid motion 2009.