Incommensurate spiral magnetic order on anisotropic triangular lattice: Dynamical mean-field study in a spin-rotating frame

Article

关键词: HEISENBERG-ANTIFERROMAGNET;    APPROXIMATION;    SYSTEMS;    MODELS;    PHASES;   

DOI  :  10.1103/PhysRevB.94.245145

来源: SCIE

【 摘 要 】

We study the ground-state magnetism of the half-filled Hubbard model on the anisotropic triangular lattice, where two out of three bonds have hopping t and the third one has t' in a unit triangle. Working in a spin-rotating frame and using the density matrix renormalization group method as an impurity solver, we provide a proper description of incommensurate magnetizations at zero temperature in the framework of the dynamical mean-field theory (DMFT). It is shown that the incommensurate spiral magnetic order for t'/t greater than or similar to 0.7 survives the dynamical fluctuations of itinerant electrons in the Hubbard interaction range from the strong-coupling (localized-spin) limit down to the insulator-to-metal transition. We also find that when the anisotropy parameter t'/t increases from the Neel-to-spiral transition, the magnitude of the magnetic moment exhibits a maximum at the isotropic triangular lattice point t'/t = 1 and then rapidly decreases in the range of larger t'/t. This work gives a solid foundation for further extension of the study including nonlocal correlation effects neglected at the standard DMFT level.

【 授权许可】

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