Renormalization group analysis of magnetic and superconducting instabilities near van Hove band fillings

Article

关键词: 2-DIMENSIONAL HUBBARD-MODEL;    WAVE SUPERCONDUCTIVITY;    CORRELATED ELECTRONS;    SPIN FLUCTUATIONS;    NEAREST-NEIGHBOR;    PHASE-SEPARATION;    FERMI-SURFACE;    2 DIMENSIONS;    FERROMAGNETISM;    SR2RUO4;   

DOI  :  10.1103/PhysRevB.68.195101

来源: SCIE

【 摘 要 】

Phase diagrams of the two-dimensional one-band t-t' Hubbard model are obtained within the two-patch and temperature-cutoff many-patch renormalization group approaches. At small t' and at van Hove band fillings antiferromagnetism dominates, while with increasing t' or changing filling antiferromagnetism is replaced by d-wave superconductivity. Near t' = t/2 and close to van Hove band fillings the system is unstable towards ferromagnetism. Away from van Hove band fillings this ferromagnetic instability is replaced by a region with dominating triplet p-wave superconducting correlations. The results of the renormalization-group approach are compared with the mean-field results and the results of the T-matrix approximation.

【 授权许可】

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