Mott transition and magnetism of the triangular-lattice Hubbard model with next-nearest-neighbor hopping

Article

关键词: ENERGY-FUNCTIONAL APPROACH;    HEISENBERG-ANTIFERROMAGNET;    INSULATOR;    SUPERCONDUCTIVITY;    DISORDER;    ORDER;   

DOI  :  10.1103/PhysRevB.95.075124

来源: SCIE

【 摘 要 】

The variational cluster approximation is used to study the isotropic triangular-lattice Hubbard model at half filling, taking into account the nearest-neighbor (t(1)) and next-nearest-neighbor (t(2)) hopping parameters for magnetic frustrations. We determine the ground-state phase diagram of the model. In the strong-correlation-regime, the 120 degrees Neel-and stripe-ordered phases appear, and a nonmagnetic insulating phase emerges in between. In the intermediate correlation regime, the nonmagnetic insulating phase expands to a wider parameter region, which goes into a paramagnetic metallic phase in the weak-correlation regime. The critical phase boundary of the Mott metal-insulator transition is discussed in terms of the van Hove singularity evident in the calculated density of states and single-particle spectral function.

【 授权许可】

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