Forcing Ferromagnetic Coupling Between Rare-Earth-Metal and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mn>3</mml:mn><mml:mi>d</mml:mi></mml:math>Ferromagnetic Films

Abstract

Using density functional calculations, we have studied the magnetic properties of nanocomposites composed of rare-earth-metal elements in contact with $3d$ transition metals (Fe and Cr). We demonstrate the possibility to obtain huge magnetic moments in such nanocomposites, of order $10{\ensuremath{\mu}}_{B}/\phantom{\rule{0ex}{0ex}}\mathrm{\text{rare-earth-metal atom}}$, with a potential to reach the maximum magnetic moment of Fe-Co alloys at the top of the so-called Slater-Pauling curve. A first experimental proof of concept is given by thin-film synthesis of $\mathrm{Fe}/\mathrm{Gd}$ and $\mathrm{Fe}/\mathrm{Cr}/\mathrm{Gd}$ nanocomposites, in combination with x-ray magnetic circular dichroism.