Field-induced magnetic anisotropy in La0.7Sr0.3CoO3
Abstract
Magnetic anisotropy has been measured for the ferromagnetic La0.7Sr0.3CoO3 perovskite from an analysis of the high-field part of the magnetization vs. field curves, i.e., the magnetic saturation regime. These measurements give a magnetic anistropy one order of magnitude higher than that of reference manganites. Surprisingly, the values of the magnetic anisotropy calculated in this way do not coincide with those estimated from measurements of coercive fields which are one order of magnitude smaller. It is proposed that the reason of this anomalous behaviour is a transition of the trivalent Co ions under the external magnetic field from a low-spin to an intermediate-spin state. Such a transition converts the Co3+ ions into Jahn-Teller ions having an only partially quenched orbital angular momentum, which enhances the intra-atomic spin-orbit coupling and magnetic anisotropy.
- Publication:
-
EPL (Europhysics Letters)
- Pub Date:
- May 2003
- DOI:
- 10.1209/epl/i2003-00414-0
- arXiv:
- arXiv:cond-mat/0304211
- Bibcode:
- 2003EL.....62..433M
- Keywords:
-
- 75.30.Gw;
- 75.30.Cr;
- 71.70.Ej;
- Magnetic anisotropy;
- Saturation moments and magnetic susceptibilities;
- Spin-orbit coupling Zeeman and Stark splitting Jahn-Teller effect;
- Condensed Matter - Strongly Correlated Electrons;
- Condensed Matter - Materials Science
- E-Print:
- Accepted of publication in Europhysics Letters, 11 pages, 5 figures