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Current localization and Joule self-heating effects in Cr doped Nd0.5Ca0.5MnO3 manganites

A. S. Carneiro·R. F. Jardim·F. C. Fonseca
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Abstract

The effects of dc excitation current on the current-voltage curves of polycrystalline samples of Nd0.5Ca0.5Mn0.96Cr0.04O3 were investigated. The experimental results show that an abrupt jump of the voltage is concomitant with a huge increase in the temperature of the sample. A simple model and estimates for Joule self-heating effects support the experimental data. Moreover, the data strongly suggest that both the current localization in the metallic paths and local Joule self-heating effects are essential ingredients to understand the current-induced phase transition in phase-separated manganites.

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A. S. Carneiro, R. F. Jardim, F. C. Fonseca. 2006-01-16. Current localization and Joule self-heating effects in Cr doped Nd0.5Ca0.5MnO3 manganites. https://doi.org/10.1103/physrevb.73.012410

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