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arXiv · 2102.03587

Collective formation of misfit dislocations at the critical thickness for equilibrium nanowire heterostructures

Thue Christian Thann·Tobias Særkjær·Sergej Schuwalow·Peter Krogstrup
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Abstract

In this work we model the evolution of strain energy during different growth stages of heterostructure nanowires. We find that the minimum energy configuration changes abruptly from fully elastically strained to partially relaxed due to collective formation of a misfit dislocation network. The transition at the critical thickness is associated with a characteristic density of misfits. These insights are gained from a technique developed to simulate misfit dislocations in a finite element framework, incorporating both elastic and plastic relaxation in a stationary heterostructure. We argue that these results have general relevance for mismatched heterostructures.

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Thue Christian Thann, Tobias Særkjær, Sergej Schuwalow, Peter Krogstrup. 2021-02-06. Collective formation of misfit dislocations at the critical thickness for equilibrium nanowire heterostructures. https://arxiv.org/abs/2102.03587

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