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Crystallography on curved surfaces.

ABSTRACT: We study static and dynamical properties that distinguish 2D crystals constrained to lie on a curved substrate from their flat-space counterparts. A generic mechanism of dislocation unbinding in the presence of varying Gaussian curvature is presented in the context of a model surface amenable to full analytical treatment. We find that glide diffusion of isolated dislocations is suppressed by a binding potential of purely geometrical origin. Finally, the energetics and biased diffusion dynamics of point defects such as vacancies and interstitials are explained in terms of their geometric potential.

SUBMITTER: Vitelli V

PROVIDER: S-EPMC1533801 | biostudies-literature | 2006 Aug

REPOSITORIES: biostudies-literature

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Crystallography on curved surfaces.

Vitelli Vincenzo V Lucks J B JB Nelson D R DR

Proceedings of the National Academy of Sciences of the United States of America 20060807 33

We study static and dynamical properties that distinguish 2D crystals constrained to lie on a curved substrate from their flat-space counterparts. A generic mechanism of dislocation unbinding in the presence of varying Gaussian curvature is presented in the context of a model surface amenable to full analytical treatment. We find that glide diffusion of isolated dislocations is suppressed by a binding potential of purely geometrical origin. Finally, the energetics and biased diffusion dynamics o ...[more]

PMID: 16894160

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