Direct observation of the interlayer exchange coupling mechanism in a magnetic [Er|Tb] multilayer

• Published in: Europhysics letters Vol. 65; no. 4; pp. 560 - 566
• Main Authors: Voigt, J, Kentzinger, E, Rücker, U, Wermeille, D, Hupfeld, D, Schweika, W, Schmidt, W, Brückel, Th
• Format: Journal Article
• Language: English
• Published: IOP Publishing 01.02.2004; EDP Sciences
• Subjects: 61.18.Fs; 75.25.+z; 75.75.+a
• ISSN: 0295-5075; 1286-4854
• DOI: 10.1209/epl/i2003-10111-6

Proximity effects in an [$\chem{Er_{20}|Tb_{5}}$] superlattice lead to the formation of new magnetic phases. Modulated magnetic order, expected for pure $\chem{Er}$, and ferromagnetic order, expected for pure $\chem{Tb}$, coexist at low temperatures. Employing X-ray resonance exchange scattering, we could probe directly the respective spin polarisations of the conduction band electrons, providing a mechanism for the interlayer coupling. The different anisotropies of $\chem{Er}$ and $\chem{Tb}$ compete with this tendency to long-range magnetic order, leading to substantial thermal-hysteresis effects.