Correlation between electrical and magnetic properties of phase separated manganites studied with a general effective medium model

JOAQUIN SACANELL; MARIANO QUINTERO; FRANCISCO PARISI,; LUIS GHIVELDER,; ANA GABRIELA LEYVA; PABLO LEVY,

PHYSICA B - CONDENSED MATTER

ELSEVIER SCIENCE BV

Año: 2007 vol. 398 p. 238 - 240

0921-4526

We have performed electrical resistivity and DC magnetization measurements as a function of temperature, on polycrystalline samples of phase-separated La5/8yPryCa3/8MnO3 (y ¼ 0.3). We have used the general effective medium theory to obtain theoretical resistivity vs. temperature curves corresponding to different fixed ferromagnetic (FM) 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 FM 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.5/8yPryCa3/8MnO3 (y ¼ 0.3). We have used the general effective medium theory to obtain theoretical resistivity vs. temperature curves corresponding to different fixed ferromagnetic (FM) 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 FM 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.