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arXiv · 1711.06780

Local melting attracts grain boundaries in colloidal polycrystals

Caitlin Cash·Jeremy Wang·Maya Martirossyan·B. Kemper Ludlow·Alejandro E. Baptista·Nina M. Brown·Eli J. Weissler·Jatin Abacousnac·Sharon J. Gerbode
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Abstract

We find that laser-induced local melting attracts and deforms grain boundaries in 2D colloidal crystals. When a melted region in contact with the edge of a crystal grain recrystallizes, it deforms the grain boundary --- this attraction is driven by the multiplicity of deformed grain boundary configurations. Furthermore, the attraction provides a method to fabricate artificial colloidal crystal grains of arbitrary shape, enabling new experimental studies of grain boundary dynamics and ultimately hinting at a novel approach for fabricating materials with designer microstructures.

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Caitlin Cash, Jeremy Wang, Maya Martirossyan, B. Kemper Ludlow, Alejandro E. Baptista, Nina M. Brown, Eli J. Weissler, Jatin Abacousnac, Sharon J. Gerbode. 2017-11-18. Local melting attracts grain boundaries in colloidal polycrystals. https://doi.org/10.1103/physrevlett.120.018002

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