Phase diagram of the Hubbard-Kondo lattice model from the variational cluster approximation

Article

关键词: CONDUCTION ELECTRONS;    MAGNETIC IMPURITY;    LUTTINGER LIQUID;    FIELD-THEORY;    ANDERSON;    SYSTEMS;    TRANSITIONS;    DIMENSIONS;    ENERGY;    SPIN;   

DOI  :  10.1103/PhysRevB.97.235151

来源: SCIE

【 摘 要 】

The interplay between the Kondo effect and magnetic ordering driven by the Ruderman-Kittel-Kasuya-Yosida interaction is studied within the two-dimensional Hubbard-Kondo lattice model. In addition to the antiferromagnetic exchange interaction J(perpendicular to) between the localized spins and the conduction electrons, this model also contains the local repulsion U between the conduction electrons. We use variational cluster approximation to investigate the competition between the antiferromagnetic phase, the Kondo singlet phase, and a ferrimagnetic phase on square lattice. At half-filling, the Neel antiferromagnetic phase dominates from small to moderate J(perpendicular to) and U J(perpendicular to) , and the Kondo singlet elsewhere. Sufficiently away from half-filling, the antiferromagnetic phase first gives way to a ferrimagnetic phase (in which the localized spins order ferromagnetically, and the conduction electrons do likewise, but the two mutually align antiferromagnetically), and then to the Kondo singlet phase.

【 授权许可】

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