title: Mode selection in the spontaneous motion of an alcohol droplet.
abstract: An alcohol (pentanol) droplet exhibits spontaneous motion on an aqueous solution, driven by a solutal Marangoni effect. We found that the droplets mode of motion is controlled by its volume. A droplet with a volume of less than 0.1 microl shows irregular translational motion, whereas intermediate-sized droplets of 0.1-200 microl show vectorial motion. When the volume is above 300 microl, the droplet splits into smaller drops. These experimental results regarding mode selection are interpreted in terms of the wave-number selection depending on the droplet volume.
authors.affiliation: Department of Physics, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Nagai
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Sumino
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kitahata
authors.forename: Kenichi
authors.initials: K
authors.lastname: Yoshikawa