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arXiv · 2304.07105

Escape from the Second Dimension: A Topological Distinction Between Edge and Screw Dislocations

Paul G. Severino·Randall D. Kamien
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Abstract

Volterra's definition of dislocations in crystals distinguishes edge and screw defects geometrically, according to whether the Burgers vector is perpendicular or parallel to the defect. Here, we demonstrate a distinction between screw and edge dislocations that enables a unified, purely topological means of classification. Our construction relies on the construction of real or virtual disclination-line pairs at the core of the dislocation in a smectic and can be generalized to crystals with triply-periodic order. The connection between topology and geometry is exploited.

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Paul G. Severino, Randall D. Kamien. 2023-04-14. Escape from the Second Dimension: A Topological Distinction Between Edge and Screw Dislocations. https://arxiv.org/abs/2304.07105

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