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arXiv · 0810.4081

Itinerant Ferromagnetism in the electronic localization limit

N. Kurzweil·E. Kogan·A. Frydman
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Abstract

We present Hall effect, $R_{xy}(H)$, and magnetoresistance, $R_{xx}(H)$, measurements of ultrathin films of Ni, Co and Fe with thicknesses varying between 0.2-8 nm and resistances between 1 M$Ω$ - 100 $Ω.$ Both measurements show that films having resistance above a critical value, $R_{C}$, (thickness below a critical value, $d_{C}$) show no signs for ferromagnetism. Ferromagnetism appears only for films with $R<R_{C}$, where $R_{C}$ is material dependent. We raise the possibility that the reason for the absence of spontaneous magnetization is suppression of itinerant ferromagnetism by electronic disorder in the strong localization regime.

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N. Kurzweil, E. Kogan, A. Frydman. 2009-02-02. Itinerant Ferromagnetism in the electronic localization limit. https://doi.org/10.1103/physrevlett.102.096603

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