The perpendicular anisotropy of multilayered Fe/Tb films (abstract)
- Institute fuer Angewandte Physik Universitaet, W-8400 Regensburg (Germany)
Multilayer Fe/Tb films were produced by rf sputtering. The thickness ratio of the Fe and Tb single layers was chosen in such kind to give an overall concentration of about 20 at. % Tb. Homogenous amorphous films of such a composition are well known for their perpendicular anisotropy. The investigations in the magnetic properties revealed that the multilayer films showed perpendicular anisotropy much stronger than the homogenous amorphous films. The maximum of the perpendicular anisotropy was found for multilayers with thickness combination of the single layers {ital t}{sub Fe}=1.0 nm, {ital t}{sub Tb}=1.5 nm. The perpendicular anisotropy increases strongly with increasing substrate temperature during rf sputtering. From the results of VSM measurements of the magnetic moment of the samples we must conclude that the Tb single layers are magnetically ordered even at room temperature. The magnetic moment of the Tb film is antiparallel coupled to the moment of the Fe film. The range of the coupling is at least 2 nm. As long as the multilayer films with various thicknesses of the single layers show perpendicular anisotropy, this anisotropy is rather independent of the thickness of the Tb layers but shows a linear dependence of the reciprocal of the thickness of the Fe layers. The magnetic investigations were accompanied by structural investigations. X-ray diffraction shows very clearly the superlattice of the multilayer films. Observations of cross sections of the multilayers by high-resolution electron microscopy revealed very sharp interfaces between Fe and Tb. The Tb films are crystallographically well ordered, whilst the Fe films showed only a nanocrystalline order. Moesbauer investigations are carried out to give an insight in the influence of the Tb films on the hyperfine field at the Fe atoms.
- OSTI ID:
- 5164379
- Journal Information:
- Journal of Applied Physics; (United States), Journal Name: Journal of Applied Physics; (United States) Vol. 70:10; ISSN 0021-8979; ISSN JAPIA
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structural anisotropy in amorphous Fe-Tb thin films
Structural origins of magnetic anisotropy in sputtered amorphous Tb-Fe films