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arXiv · 0709.1631

Size-dependent Surface States on Strained Cobalt Nanoislands on Cu(111)

M. V. Rastei·B. Heinrich·L. Limot·P. A. Ignatiev·V. S. Stepanyuk·P. Bruno·J. P. Bucher
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Abstract

Low-temperature scanning tunneling spectroscopy over Co nanoislands on Cu(111) showed that the surface states of the islands vary with their size. Occupied states exhibit a sizeable downward energy shift as the island size decreases. The position of the occupied states also significantly changes across the islands. Atomic-scale simulations and ab inito calculations demonstrate that the driving force for the observed shift is related to size-dependent mesoscopic relaxations in the nanoislands.

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M. V. Rastei, B. Heinrich, L. Limot, P. A. Ignatiev, V. S. Stepanyuk, P. Bruno, J. P. Bucher. 2007-09-11. Size-dependent Surface States on Strained Cobalt Nanoislands on Cu(111). https://doi.org/10.1103/physrevlett.99.246102

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