Europhys. Lett.
Volume 72, Number 5, December 2005
Page(s) 809 - 815
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 03 November 2005
Europhys. Lett., 72 (5), pp. 809-815 (2005)
DOI: 10.1209/epl/i2005-10308-7

Comparisons of the high- and low-field magnetic anisotropies in a single-crystal manganite and a polycrystalline cobaltite

T. Brown1, Wei Li1, X. Z. Zhou1, H. P. Kunkel1, Gwyn Williams1, Y. Mukovskii2 and D. Shulyatev2

1  Department of Physics and Astronomy, University of Manitoba Winnipeg, MB R3T 2N2, Canada
2  Moscow State Steel and Alloys Institute - Lenin Prosp. 4, Moscow 119991, Russia

received 10 May 2005; accepted in final form 4 October 2005
published online 3 November 2005

The approach to magnetic saturation has been used to estimate the magnetic anisotropy in single-crystal La0.73Ba0.27MnO3 and polycrystalline La0.5Sr0.5CoO3, and these estimates are compared with those found from the measured coercive field. While this analysis confirms the order-of-magnitude discrepancy between these two estimates reported previously and linked, via the enhanced anisotropic magnetostrictive behaviour, to a field-induced low- to high-spin state transition of the Co ion, it also indicates that such discrepancies may be a ubiquitous feature of these transition metal oxides, occurring in systems where orbital instabilities appear unlikely.

75.30.Gw - Magnetic anisotropy.
75.30.Cr - Saturation moments and magnetic susceptibilities.
71.70.Ej - Spin-orbit coupling, Zeeman and Stark Splitting, Jahn-Teller effect.

© EDP Sciences 2005