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arXiv · 2108.07469

Avalanches and Structural Change in Cyclically Sheared Silica Glass

Himangsu Bhaumik·Giuseppe Foffi·Srikanth Sastry
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Abstract

We investigate avalanches associated with plastic rearrangements and the nature of structural change in the prototypical strong glass, silica, computationally. Although qualitative aspects of yielding in silica are similar to other glasses, we find that the statistics of avalanches exhibits non-trivial behaviour. Investigating the statistics of avalanches and clusters in detail, we propose and verify a new relation between exponents characterizing the size distribution of avalanches and clusters. Across the yielding transition, anomalous structural change and densification, associated with a suppression of tetrahedral order, is observed to accompany strain localisation.

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Himangsu Bhaumik, Giuseppe Foffi, Srikanth Sastry. 2021-08-17. Avalanches and Structural Change in Cyclically Sheared Silica Glass. https://doi.org/10.1103/physrevlett.128.098001

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