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Effect of Ga doping on magnetotransport properties in collosal magnetoresistive La0.7Ca0.3Mn1-xGaxO3 (0 < x < 0.1)

Marek Pekala·Jan Mucha·Benedicte Vertruyen·Rudi Cloots·Marcel Ausloos
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Abstract

Samples of La0.7Ca0.3Mn1-xGaxO3 with x = 0, 0.025, 0.05 and 0.10 were prepared by standard solid-state reaction. They were first characterized chemically, including the microstructure. The magnetic properties and various transport properties, i.e. the electrical resistivity, magnetoresistivity (for a field below 8T), thermoelectric power and thermal conductivity measured each time on the same sample, are reported. The markedly different behavior of the x = 0.1 sample from those with a smaller Ga content, is discussed. The dilution of the Mn3+/Mn4+ interactions with Ga doping considerably reduces the ferromagnetic double exchange interaction within the manganese lattice leading to a decrease of the Curie temperature. The polaron binding energy varies from 224 to 243 meV with increased Ga doping.

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Marek Pekala, Jan Mucha, Benedicte Vertruyen, Rudi Cloots, Marcel Ausloos. 2006-06-16. Effect of Ga doping on magnetotransport properties in collosal magnetoresistive La0.7Ca0.3Mn1-xGaxO3 (0 < x < 0.1). https://doi.org/10.1016/j.jmmm.2006.02.241

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