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The effect of Cu-doping on the magnetic and transport properties of La0.7Sr0.3MnO3

M. S. Kim·J. B. Yang·Q. Cai·X. D. Zhou·W. J. James·W. B. Yelon·P. E. Parris·D. Buddhikot·S. K. Malik
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Abstract

The effects of Cu-doping on the structural, magnetic, and transport properties of La0.7Sr0.3Mn1-xCuxO3 (0 < x < 0.20) have been studied using neutron diffraction, magnetization and magnetoresistance (MR) measurements. All samples show the rhombohedral structure with the R3c space-group from 10K to room temperature (RT). Neutron diffraction data suggest that some of the Cu ions have a Cu3+ state in these compounds. The substitution of Mn by Cu affects the Mn-O bond length and Mn-O-Mn bond angle resulting from the minimization of the distortion of the MnO6 octahedron. Resistivity measurements show that a metal to insulator transition occurs for the x more than 0.15 samples. The x = 0.15 sample shows the highest MR(_80%), which might result from the co-existence of Cu3+/Cu2+ and the dilution effect of Cu-doping on the double exchange interaction.

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M. S. Kim, J. B. Yang, Q. Cai, X. D. Zhou, W. J. James, W. B. Yelon, P. E. Parris, D. Buddhikot, S. K. Malik. 2005-02-09. The effect of Cu-doping on the magnetic and transport properties of La0.7Sr0.3MnO3. https://doi.org/10.1063/1.1860992

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