Dislocation dynamics on deformable surfaces

Marcello De Donno; Luiza Angheluta; Marco Salvalaglio

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arXiv · 2602.14348

Dislocation dynamics on deformable surfaces

Marcello De Donno·Luiza Angheluta·Marco Salvalaglio

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Abstract

We develop a fully coupled theoretical description of dislocation dynamics on deformable crystalline surfaces, using continuum modeling and the amplitude-phase-field crystal (APFC) framework extended to curved geometries. We derive a general kinematic expression for dislocation velocity directly from the complex-amplitude evolution equations, which is also applicable to deformed surfaces through curvature-modified differential operators. From numerical simulations, we show that even small out-of-plane deformations reshape the phenomenology of defect motion through curvature-induced self-propulsion, modified glide directions, and non-classical defect-defect interactions. Our results show how surface geometry profoundly influences defect dynamics and establish the surface-APFC model as a powerful framework for predicting and interpreting curvature-defect coupling across a wide range of systems, from stiff but deformable layers to soft matter surfaces and membranes that retain crystalline order.

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Marcello De Donno, Luiza Angheluta, Marco Salvalaglio. 2026-02-15. Dislocation dynamics on deformable surfaces. https://arxiv.org/abs/2602.14348

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