Phase separation in La0.5Ca0.5MnO3 doped with 1% Sn-119 detected by Mossbauer spectroscopy

Article

关键词: NEUTRON-DIFFRACTION;    MAGNETIC-PROPERTIES;    SPIN DYNAMICS;    CHARGE;    MN-55;    ORDER;    LA1-XCAXMNO3;    TRANSITION;    MODELS;    LA-139;   

DOI  :  10.1103/PhysRevB.63.054403

来源: SCIE

【 摘 要 】

1%Sn-119-doped La0.5Ca0.5MnO3 was studied by Mossbauer spectroscopy, magnetic moment, and resistivity measurements. The Mossbauer spectra below the charge-ordering temperature are explained with ferromagnetic, antiferromagnetic. and ferromagnetic spin cluster components. The magnetic and thermal hystereses of the relative intensities of the components observed in the Mossbauer spectra, and of the bulk properties such as magnetic moment and electrical resistivity, in the temperature range 125-185 K, are characteristic of phase equilibrium in a first-order transition, i.e., of phase separation in the system below the charge-ordering transition. The cluster component displays a significant hyperfine field up to similar to 125 K. Above this temperature it exhibits superparamagnetism, becoming the dominant component above the charge-ordering transition. These results are discussed in the framework of recent investigations of the manganite system with other techniques which also show phase separation.

【 授权许可】

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