Abstract
The magnetic properties of La0.7Ca0.3MnO3 (LCMO) manganite thin films were studied with magnetometry and ferromagnetic resonance as a function of film thickness. They maintain the colossal magnetoresistance behavior with a pronounced metal-insulator transition around 150-200 K, except for the very thinnest films studied (3 nm). Nevertheless, LCMO films as thin as 3 nm remain ferromagnetic, without a decrease in saturation magnetization, indicating an absence of dead-layers, although below approximately 6 nm the films remain insulating at low temperature. Magnetization hysteresis loops reveal that the magnetic easy axes lie in the plane of the film for thicknesses in the range of 4-15 nm. Ferromagnetic resonance studies confirm that the easy axes are in-plane, and find a biaxial symmetry in-plane with two, perpendicular easy axes. The directions of the easy axes with respect to the crystallographic directions of the cubic SrTiO3 substrate differ by 45 deg in 4-and 15-nm-thick LCMO films.
Original language | English (US) |
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Pages (from-to) | 2926-2929 |
Number of pages | 4 |
Journal | IEEE Transactions on Magnetics |
Volume | 44 |
Issue number | 11 PART 2 |
DOIs | |
State | Published - Nov 2008 |
Externally published | Yes |
Bibliographical note
Funding Information:The work of N. M. Nemes was supported by a “Ramon y Cajal” fellowship funded by the Spanish Ministry of Science and Education. This work was supported in part by SPIN-MAT06024 C01 and C02 and by Marie-Curie-IRG under Grant 024861 and by OTKA PF63954, K68807, and NK60984.
Keywords
- Epitaxial layers
- Magnetic anisotropy
- Magnetic resonance
- Manganites
- Thin films