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Crystallographic structure of ultrathin Fe films on Cu(100)

Albert Biedermann·Rupert Tscheliessnig·Michael Schmid·Peter Varga
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Abstract

We report bcc-like crystal structures in 2-4 ML Fe films grown on fcc Cu(100) using scanning tunneling microscopy. The local bcc structure provides a straightforward explanation for their frequently reported outstanding magnetic properties, i.e., ferromagnetic ordering in all layers with a Curie temperature above 300 K. The non-pseudomorphic structure, which becomes pseudomorphic above 4 ML film thickness is unexpected in terms of conventional rules of thin film growth and stresses the importance of finite thickness effects in ferromagnetic ultrathin films.

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Albert Biedermann, Rupert Tscheliessnig, Michael Schmid, Peter Varga. 2001-06-19. Crystallographic structure of ultrathin Fe films on Cu(100). https://doi.org/10.1103/physrevlett.87.086103

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