2016/08/16 by Shimpei Goto, Susumu Kurihara, Daisuke Yamamoto · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Antiferromagnetism #Condensed matter physics #Hexagonal lattice #Hubbard model #Magnetic moment #Organic and Molecular Conductors Research #Physics #Physics of Superconductivity and Magnetism #Quantum mechanics #Superconductivity #cond-mat.str-el
paper · pdf · doi:10.1103/physrevb.94.245145
published as Phys. Rev. B 94, 245145 (2016) · 8 pages, 7 figures
arxiv created 2016/08/16 · openalex created_date 2016/09/16 · openalex publication_date 2016/12/28 · arxiv updated 2017/01/04 · openalex updated_date 2026/08/05
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^\ensuremath' 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^\ensuremath'/t\ensuremath\gtrsim0.7 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^\ensuremath'/t increases from the N'eel-to-spiral transition, the magnitude of the magnetic moment exhibits a maximum at the isotropic triangular lattice point t^\ensuremath'/t=1 and then rapidly decreases in the range of larger t^\ensuremath'/t. This work gives a solid foundation for further extension of the study including nonlocal correlation effects neglected at the standard DMFT level.