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Anomalous Hall Effect of Calcium-doped Lanthanum Cobaltite Films

S. A. Baily·M. B. Salamon
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Abstract

The Hall resistivity, magnetoresistance, and magnetization of La_{1-x}Ca_{x}CoO_{3} epitaxial films with x between 0.25 and 0.4 grown on lanthanum aluminate were measured in fields up to 7 T. The x=1/3 film, shows a reentrant metal insulator transition. Below 100 K, the x=1/3 and 0.4 films have significant coercivity which increases with decreasing temperature. At low temperature the Hall resistivity remains large and essentially field independent in these films, except for a sign change at the coercive field that is more abrupt than the switching of the magnetization. A unique magnetoresistance behavior accompanies this effect. These results are discussed in terms of a percolation picture and the mixed spin state model for this system. We propose that the low-temperature Hall effect is caused by spin-polarized carriers scattering off of orbital disorder in the spin-ordered clusters.

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S. A. Baily, M. B. Salamon. 2002-08-27. Anomalous Hall Effect of Calcium-doped Lanthanum Cobaltite Films. https://doi.org/10.1063/1.1540183

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