Renormalization group analysis of magnetic and superconducting instabilities near van Hove band fillings
نویسندگان
چکیده
Phase diagrams of the two-dimensional one-band t-t8 Hubbard model are obtained within the two-patch and temperature-cutoff many-patch renormalization group approaches. At small t8 and at van Hove band fillings antiferromagnetism dominates, while with increasing t8 or changing filling antiferromagnetism is replaced by d-wave superconductivity. Near t85t/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.
منابع مشابه
2 00 3 Renormalization group analysis of magnetic and superconducting instabilities near van Hove band fillings
Phase diagrams of the two-dimensional one-band t-t ′ Hubbard model are obtained within the two-patch and the temperature-cutoff many-patch renor-malization group approach. At small t ′ and at van Hove band fillings anti-ferromagnetism dominates, while with increasing t ′ or changing filling anti-ferromagnetism is replaced by d-wave superconductivity. Near t ′ = t/2 and close to van Hove band fi...
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