Effect of compositional homogeneity on the magnetic propertiesof La_0.7Ca_0.3MnO₃

Abstract

Dc magnetization and ac magnetic susceptibility have been measured in the temperature range 80–300 K for La_0.7Ca_0.3MnO₃ , synthesized by the conventional ceramic and the low temperature combustion methods and annealed at different temperatures. Temperature dependence of the dc magnetization and the ac susceptibility is strongly dependent on the processing conditions resulting in compositional inhomogeneity in the samples. A sharp ferromagnetic transition is observed only for a compositionally homogeneous sample.

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