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arXiv · 1712.05041

Step bunching with both directions of the current: Vicinal W(110) surfaces versus atomistic scale model

Olzat Toktarbaiuly·Victor Usov·Cormac Ó Coileáin·Katarzyna Siewierska·Sergey Krasnikov·Emma Norton·Sergey I. Bozhko·Valery N. Semenov·Alexander N. Chaika·Barry E. Murphy·Olaf Lübben·Filip Krzyżewski·Magdalena A. Załuska-Kotur·Anna Krasteva·Hristina Popova·Vesselin Tonchev·Igor V. Shvets
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Abstract

We report for the first time the observation of bunching of monoatomic steps on vicinal W(110) surfaces induced by step up or step down currents across the steps. Measurements reveal that the size scaling exponent γ, connecting the maximal slope of a bunch with its height, differs depending on the current direction. We provide a numerical perspective by using an atomistic scale model with a conserved surface flux to mimic experimental conditions, and also for the first time show that there is an interval of parameters in which the vicinal surface is unstable against step bunching for both directions of the adatom drift.

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Olzat Toktarbaiuly, Victor Usov, Cormac Ó Coileáin, Katarzyna Siewierska, Sergey Krasnikov, Emma Norton, Sergey I. Bozhko, Valery N. Semenov, Alexander N. Chaika, Barry E. Murphy, Olaf Lübben, Filip Krzyżewski, Magdalena A. Załuska-Kotur, Anna Krasteva, Hristina Popova, Vesselin Tonchev, Igor V. Shvets. 2017-12-31. Step bunching with both directions of the current: Vicinal W(110) surfaces versus atomistic scale model. https://doi.org/10.1103/physrevb.97.035436

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