Double-expansion impurity solver for multiorbital models with dynamically screened U and J

Article

关键词: MEAN-FIELD THEORY;    INFINITE DIMENSIONS;    ORBITAL DEGENERACY;    MOTT TRANSITION;    SUPERCONDUCTIVITY;    FERROMAGNETISM;    FULLERIDES;    SYSTEMS;    STATE;   

DOI  :  10.1103/PhysRevB.92.115123

来源: SCIE

【 摘 要 】

We present a continuous-time Monte Carlo impurity solver for multiorbital impurity models which combines a strong-coupling hybridization expansion and a weak-coupling expansion in the Hund's coupling parameter J. This double-expansion approach allows to treat the dominant density-density interactions U within the efficient segment representation. We test the approach for a two-orbital model with static interactions, and then explain how the double expansion allows to simulate models with frequency dependent U(omega) and J (omega). The method is used to investigate spin-state transitions in a toy model for fullerides, with repulsive bare J but attractive screened J.

【 授权许可】

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