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Magnetotransport in a bi-crystal film of La_0.7Sr_0.3MnO_3

R. Mathieu·P. Svedlindh·R. Chakalov·Z. G. Ivanov
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Abstract

Transport properties of an epitaxial film of La_0.7Sr_0.3MnO_3 (LSMO), deposited epitaxially on a LaAlO_3 bi-crystal substrate having a misorientation angle of 9.2 deg., have been studied. The film was patterned into a meander containing 100 grain boundaries. The resistivity of the sample exhibits two components; one originating from the grain boundary regions, and one from the LSMO elements in the meander; the latter contribution is similar to the resistivity of a reference epitaxial LSMO film. The low (<0.5 T) and high (up to 6 T) field magnetoresistance was also studied. The meander show a large low field magnetoresistance, increasing with decreasing temperature, and a constant high field slope of the magnetoconductance, results that are well explained by a two-step spin polarized tunneling model.

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R. Mathieu, P. Svedlindh, R. Chakalov, Z. G. Ivanov. 2001-09-04. Magnetotransport in a bi-crystal film of La_0.7Sr_0.3MnO_3. https://doi.org/10.1016/s0304-8853(00)00860-x

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