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