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Self-assembly of iron nanoclusters on the Fe3O4(111) superstructured surface

N. Berdunov·G. Mariotto·S. Murphy·I. V. Shvets
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Abstract

We report on the self-organized growth of a regular array of Fe nanoclusters on a nanopatterned magnetite surface. Under oxidizing preparation conditions the (111) surface of magnetite exhibits a regular superstructure with three-fold symmetry and a 42 A periodicity. This superstructure represents an oxygen terminated (111) surface, which is reconstructed to form a periodically strained surface. This strain patterned surface has been used as a template for the growth of an ultrathin metal film. A Fe film of 0.5 A thickness was deposited on the substrate at room temperature. Fe nanoclusters are formed on top of the surface superstructure creating a regular array with the period of the superstructure. We also demonstrate that at least the initial stage of Fe growth occurs in two-dimensional mode. In the areas of the surface where the strain pattern is not formed, random nucleation of Fe was observed.

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N. Berdunov, G. Mariotto, S. Murphy, I. V. Shvets. 2004-07-16. Self-assembly of iron nanoclusters on the Fe3O4(111) superstructured surface. https://doi.org/10.1103/physrevb.71.113406

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