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arXiv · 0811.0384

Critical thickness for itinerant ferromagnetism in ultrathin films of SrRuO$_3$

Jing Xia·W. Siemons·G. Koster·M. R. Beasley·A. Kapitulnik
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Abstract

Ultrathin films of the itinerant ferromagnet SrRuO$_3$ were studied using transport and magnto-optic polar Kerr effect. We find that below 4 monolayers the films become insulating and their magnetic character changes as they loose their simple ferromagnetic behavior. We observe a strong reduction in the magnetic moment which for 3 monolayers and below lies in the plane of the film. Exchange-bias behavior is observed below the critical thickness, and may point to induced antiferromagnetism in contact with ferromagnetic regions.

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Jing Xia, W. Siemons, G. Koster, M. R. Beasley, A. Kapitulnik. 2008-11-03. Critical thickness for itinerant ferromagnetism in ultrathin films of SrRuO$_3$. https://doi.org/10.1103/physrevb.79.140407

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