Adatom-induced dislocation annihilation in epitaxial silicene

Antoine Fleurence; Yukiko Yamada-Takamura

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arXiv · 2010.07519

Adatom-induced dislocation annihilation in epitaxial silicene

Antoine Fleurence·Yukiko Yamada-Takamura

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Abstract

The transformation of the stripe domain structure of spontaneously-formed epitaxial silicene on ZrB$_2$ thin film into a single-domain driven by the adsorption of a fraction of a monolayer of silicon was used to investigate how dislocations react and eventually annihilate in a two-dimensional honeycomb structure. The in-situ real time STM monitoring of the evolution of the domain structure after Si deposition revealed the mechanisms leading to the nucleation of a single-domain into a domain structure through a stepwise reaction of partial dislocations. After its nucleation, the single-domain extends by the propagation of edge dislocations at its frontiers. The identification of this particular nucleation-propagation formation of dislocation-free silicene sheet provides insights into how crystallographic defects can be healed in two-dimensional materials.

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Antoine Fleurence, Yukiko Yamada-Takamura. 2020-10-15. Adatom-induced dislocation annihilation in epitaxial silicene. https://arxiv.org/abs/2010.07519

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