Conductivity behavior of La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ in vicinity of ferromagnetic-paramagnetic transition studied with single current pulses

V. B. Krasovitsky; B. I. Belevtsev

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arXiv · 0804.2806

Conductivity behavior of La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ in vicinity of ferromagnetic-paramagnetic transition studied with single current pulses

V. B. Krasovitsky·B. I. Belevtsev

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Abstract

Temperature and current dependences of resistivity of bulk La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ sample grown by the floating-zone method were studied using single ramp pulses of current. It is found that near the Curie temperature $T_C$ the sample resistance depends substantially on current magnitude. The observed features can be determined by inhomogeneous Joule overheating due to mixed phase state of manganites near the ferromagnetic-paramagnetic transition and percolation character of this transition.

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V. B. Krasovitsky, B. I. Belevtsev. 2008-04-17. Conductivity behavior of La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ in vicinity of ferromagnetic-paramagnetic transition studied with single current pulses. https://arxiv.org/abs/0804.2806

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