Structure and magnetic properties of nanostructured GdTb thin films

Abstract

Various series of Gd100−xTbx films and multilayers with a different thickness of rare earth (RE) layers were prepared by rf‐sputtering. The increase of Gd content leads to an increase of the magnetic ordering temperature (Tord). At the same time substitution of the low anisotropic gadolinium by high anisotropic terbium causes an increase of the coercivity of the samples. The decrease of the RE layer thickness (LRE) results in the change of the RE films structure: the crystalline grain size goes down and for LRE < 3 nm an amorphous phase appears. For LRE < 5 nm all compositions show a significant decrease of the ordering temperature. In contrast with bulk Gd100−xTbx alloys, in case of thin films, the value of Tord can be tailored, not only by the change of the composition, but also by the variation of the thickness of Gd100−xTbx films.

Magnetocaloric effect in epitaxial La0.56Sr0.44MnO3 alloy and digital heterostructures

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