Effect of surface on the dissociation of perfect dislocations into Shockley partials describing the herringbone Au(1 1 1) surface reconstruction

Abstract

In the framework of the continuum elastic theory, the equilibrium positions of Shockley partial dislocations have been determined as a function of their distance from the free surface. It is found that the dissociation width decreases with the decreasing depth, except for a depth range very close to the free surface for which the dissociation width is enlarged. A similar behaviour is also predicted when Shockley dislocation pairs are regularly arranged, whatever the wavelength. These results derived from the elastic theory are compared to STM observations of the reconstructed (1 1 1) surface in gold, which is usually described by a Shockley dislocations network.

Keywords:

• Crystal defects
• dislocation theory
• elasticity theory
• free surface reconstruction

Acknowledgements

The author would like to thank the scholarship European Program Erasmus Mundus Al Idrisi II for the financial supports. We are also grateful to M. Drouet and PhD student D. Chauraud for their help and expertise in STM investigations, which greatly assisted this research.

Notes

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was partially funded by the French Government program Investissements d’Avenir [LABEX INTERACTIFS grant number ANR-11-LABX-0017-01].