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arXiv · 2009.03408

Statistical Mechanics of Low Angle Grain Boundaries in Two Dimensions

Grace H. Zhang·David R. Nelson
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Abstract

We explore order in low angle grain boundaries (LAGBs) embedded in a two-dimensional crystal at thermal equilibrium. Symmetric LAGBs subject to a periodic Peierls potential undergo, with increasing temperatures, a thermal depinning transition, above which the potential is irrelevant at long wavelengths and the LAGB exhibits transverse fluctuations that grow logarithmically with inter-dislocation distance. Longitudinal fluctuations lead to a series of melting transitions marked by the sequential disappearance of diverging algebraic Bragg peaks with universal critical exponents. Aspects of our theory are checked by a mapping onto random matrix theory.

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BibTeXRIS

Grace H. Zhang, David R. Nelson. 2020-09-07. Statistical Mechanics of Low Angle Grain Boundaries in Two Dimensions. https://doi.org/10.1103/physrevlett.125.215503

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