Tailoring magnetic anisotropy in epitaxial half metallic La0.7Sr0.3MnO3 thin films

Paolo Perna (1) , Carlos Rodrigo (2) , E. Jimenez (2) , Francisco Jose Teran (1) , N. Mikuszeit (1) , Laurence Méchin (3) , Julio Camarero (1, 2) , R. Minanda (1, 2)

1 Instituto IMDEA Nanociencia [Madrid]
2 Departamento de Fisica de la Materia Condensada and Instituto "Nicol as Cabrera",
3 Equipe Electronique - Laboratoire GREYC - UMR6072

We present a detailed study on the magnetic properties, including anisotropy, reversal elds, and magnetiza- tion reversal processes, of well characterized half-metallic epitaxial La0:7Sr0:3MnO3 (LSMO) thin lms grown onto SrTiO3 (STO) substrates with three di erent surface orientations, i.e. (001), (110) and (1 18). The latter shows step edges oriented parallel to the [110] (in-plane) crystallographic direction. Room temperature high resolution vectorial Kerr magnetometry measurements have been performed at di erent applied magnetic eld directions in the whole angular range. In general, the magnetic properties of the LSMO lms can be interpreted with just the uniaxial term with the anisotropy axis given by the lm morphology, whereas the strength of this anisotropy depends on both structure and lm thickness. In particular, LSMO lms grown on nominally at (110)-oriented STO substrates presents a well de ned uniaxial anisotropy originated from the existence of elongated in-plane [001]-oriented structures, whereas LSMO lms grown on nominally at (001)-oriented STO substrates show a weak uniaxial magnetic anisotropy with the easy axis direction aligned parallel to residual substrate step edges. Elongated structures are also found for LSMO lms grown on vici- nal STO(001) substrates. These lms present a well-de ned uniaxial magnetic anisotropy with the easy axis lying along the step edges and its strength increases with the LSMO thickness. It is remarkable that this step-induced uniaxial anisotropy has been found for LSMO lms up to 120 nm thickness. Our results are promising for engineering novel half-metallic magnetic devices that exploit tailored magnetic anisotropy.

Domaines: Micro et nanotechnologies/Microélectronique

Paolo Perna, Carlos Rodrigo, E. Jimenez, Francisco Jose Teran, N. Mikuszeit, et al.. Tailoring magnetic anisotropy in epitaxial half metallic La0.7Sr0.3MnO3 thin films. Journal of Applied Physics, 2011, 110 (1), pp.0139196-1 -- 10. ⟨hal-00974869⟩