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تسجيل مستخدم جديدCorrelation between electrical and magnetic properties of phase separated manganites studied with a General Effective Medium model
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We have performed electrical resistivity and DC magnetization measurements as a function of temperature, on polycrystalline samples of phase separated LaPrCaMnO. We have used the General Effective Medium Theory to obtain theoretical resistivity vs. temperature curves corresponding to different fixed ferromagnetic volume fraction values, assuming that the sample is a mixture of typical metallic like and insulating manganites. By comparing this data with our experimental resistivity curves we have obtained the relative ferromagnetic volume fraction of our sample as a function of temperature. This result matches with the corresponding magnetization data in excellent agreement, showing that a mixed phase scenario is the key element to explain both the magnetic and transport properties in the present compound.
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We have studied the irreversibility of the magnetization induced by thermal cycles in La0.5Ca0.5MnO3 manganites, which present a low temperature state characterized by the coexistence of phases. The effect is evidenced by a decrease of the magnetizat
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