Phase diagram of an extended Kondo lattice model for manganites: The Schwinger-boson mean-field approach

Article

关键词: TRANSITION-METAL OXIDES;    DOUBLE-EXCHANGE MODEL;    COLOSSAL MAGNETORESISTANCE;    MAGNETIC-FIELD;    ELECTRONIC MODELS;    MANGANESE OXIDES;    SPIRAL STATE;    LA1-XSRXMNO3;    R(1-X)A(X)MNO(3);    RESISTIVITY;   

DOI  :  10.1103/PhysRevB.61.1211

来源: SCIE

【 摘 要 】

We investigate the phase diagram of an extended Kondo lattice model for doped manganese oxides in the presence of strong but finite Hund's coupling and on-site Coulomb interaction. By means of the Schwinger-boson mean-field approach, it is found that, besides magnetic ordering, there will be nonuniform charge distributions, such as charge ordering and phase separation, if the interaction between electrons prevails over the hybridization. Which of the charge ordering and phase separation appears is determined by a competition between effective repulsive and attractive interactions due to virtual processes of electron hopping. Calculated results show that strong electron correlations caused by the on-site Coulomb interaction as well as the finite Hund's coupling play an important role in the magnetic ordering and charge distribution at low temperatures.

【 授权许可】

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