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arXiv · 0709.1581

Stability of undissociated screw dislocations in zinc-blende covalent materials from first principle simulations

Laurent Pizzagalli·Pierre Beauchamp·Jacques Rabier
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Abstract

The properties of perfect screw dislocations have been investigated for several zinc-blende materials such as diamond, Si, $β$-SiC, Ge and GaAs, by performing first principles calculations. For almost all elements, a core configuration belonging to shuffle set planes is favored, in agreement with low temperature experiments. Only for diamond, a glide configuration has the lowest defect energy, thanks to an sp$^2$ hybridization in the core.

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Laurent Pizzagalli, Pierre Beauchamp, Jacques Rabier. 2007-09-11. Stability of undissociated screw dislocations in zinc-blende covalent materials from first principle simulations. https://doi.org/10.1209/epl%2Fi2005-10259-y

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