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arXiv · 1204.5957

Singular response to a dopant of an evaporating crystal surface

Vladislav Popkov·Paolo Politi
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Abstract

Moving crystal surfaces can undergo step-bunching instabilities, when subject to an electric current. We show analytically that an infinitesimal quantity of a dopant may invert the stability, whatever the sign of the current. Our study is relevant for experimental results [S. S. Kosolobov et al., JETP Lett. 81, 117 (2005)] on an evaporating Si(111) surface, which show a singular response to Au doping, whose density distribution is related to inhomogeneous Si diffusion.

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Vladislav Popkov, Paolo Politi. 2012-04-26. Singular response to a dopant of an evaporating crystal surface. https://doi.org/10.1103/physrevb.86.161413

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