title: Alternating tip splitting in directional solidification.
abstract: We report experimental results on the tip splitting dynamics of seaweed growth in directional solidification of succinonitrile alloys. Despite the random appearance of the growth, a tip splitting morphology was observed in which the tip alternately splits to the left and to the right. The tip splitting frequency f was found to be related to the growth velocity V as a power law f~V1.5. This finding is consistent with the predictions of a tip splitting model that is also presented. Small anisotropies are shown to lead to different kinds of seaweed morphologies.
authors.affiliation: Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853, USA.
authors.forename: B
authors.initials: B
authors.lastname: Utter
authors.forename: R
authors.initials: R
authors.lastname: Ragnarsson
authors.forename: E
authors.initials: E
authors.lastname: Bodenschatz