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arXiv · 2601.22933

Resolving Structural Avalanches in Amorphous Carbon with Arclength Continuation

Fraser Birks·Ibrahim Ghanem·Lars Pastewka·James Kermode·Maciej Buze
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Abstract

Plastic deformation in amorphous solids is carried by localized shear transformations that self-organize into avalanches. In amorphous carbon modeled with a machine-learned interatomic potential, we find that the energetics and organization of these avalanches can be resolved by systematically following the underlying energy landscape. With a pseudo-arclength numerical continuation framework, we decompose avalanches into constituent shear transformations and determine their strain-dependent energetics. Our analysis shows that, prior to onset, avalanches have a latent structure that consists of well-separated local minima. We further demonstrate that arclength continuation yields an event driven framework for following avalanche dynamics, eliminating time-step effects on statistical avalanche properties such as distributions of stress drops.

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Fraser Birks, Ibrahim Ghanem, Lars Pastewka, James Kermode, Maciej Buze. 2026-01-30. Resolving Structural Avalanches in Amorphous Carbon with Arclength Continuation. https://doi.org/10.1103/6n5m-rxc1

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