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A nature of low-temperature resistivity minimum in ceramic manganites

E. Rozenberg·M. Auslender·I. Felner·G. Gorodetsky
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Abstract

Measurements of magnetoresistance and magnetization were carried out on ceramic samples of La_{0.5}Pb_{0.5}MnO_{3} and La_{0.5}Pb_{0.5}MnO_{3}, containing 10 at. % Ag in a dispersed form. The results obtained for the resistivity at zero applied magnetic field exhibit a shallow minimum at temperatures T about 25 K - 30 K, which shifts towards lower temperatures upon applying magnetic field and disappears at a certain (rather low) field. Also the resistivity at helium temperature decreases upon applying magnetic fields. It is shown that the model of spin-dependent carrier tunneling between antiferromagnetically coupled grains may account for the results observed.

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E. Rozenberg, M. Auslender, I. Felner, G. Gorodetsky. 2000-07-24. A nature of low-temperature resistivity minimum in ceramic manganites. https://doi.org/10.1063/1.1288704

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