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Magnetic-history-dependent nanostructural and resistivity changes in Pr0.5Ca0.5Mn0.98Cr0.02O3

M. Hervieu·R. Mahendiran·A. Maignan·C. Martin·B. Raveau
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Abstract

We show that nanostructure and resistivity of Pr0.5Ca0.5Mn0.98Cr0.02O3 are sensitive to whether the sample is zero-field-cooled (ZFC) of field-cooled (FC) either in the 'self magnetic field (H = 2 T)' of the electron microscope or under the external magnetic field of 2 T. FC resistivity at H = 2 T is lower than ZFC values below 140 K. The average value of the chare-orbital modulation vector (q = 0.44) of the FC crystallites is lower than that of the ZFC cystallites (q = 0.48) and the FC crystallites exhibit numerous defects like discommensuration, dislocations and regios with loss of superstructures compared to the ZFC crystallites.

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M. Hervieu, R. Mahendiran, A. Maignan, C. Martin, B. Raveau. 2000-10-26. Magnetic-history-dependent nanostructural and resistivity changes in Pr0.5Ca0.5Mn0.98Cr0.02O3. https://doi.org/10.1063/1.1321736

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