Phase diagram of the t-t '-U chain at half filling

Article

关键词: COHERENCE LENGTH SUPERCONDUCTORS;    METAL-INSULATOR-TRANSITION;    GENERALIZED HUBBARD-MODEL;    VALENCE BOND STATE;    SPIN-GAP PHASE;    NEAREST-NEIGHBOR;    PAIRING CORRELATIONS;    MAGNETIC-PROPERTIES;    FERMI-LIQUID;    LOCALIZATION;   

DOI  :  10.1103/PhysRevB.67.165102

来源: SCIE

【 摘 要 】

We study the half-filled Hubbard chain including next-nearest-neighbor hopping t('). The model has three phases: one insulating phase with dominant spin-density-wave correlations at large distances (SDWI), another phase with dominant spin-dimer correlations or dimerized insulator (DI), and a third one in which long-distance correlations indicate singlet superconductivity (SS). The boundaries of the SDWI are accurately determined numerically through a crossing of excited energy levels equivalent to the jump in the spin Berry phase. The DI-SS boundary is studied using several indicators such as correlation exponent K-rho, Drude weight D-c, localization parameter z(L), and charge gap Delta(c).

【 授权许可】

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