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arXiv · 1511.04733

Noncollinear and noncoplanar magnetic order in the extended Hubbard model on anisotropic triangular lattice

Kanika Pasrija·Sanjeev Kumar
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Abstract

Motivated by the importance of non-collinear and non-coplanar magnetic phases in determining various electrical properties of magnetic materials, we investigate the phase diagrams of the extended Hubbard model on anisotropic triangular lattice. We make use of a mean-field scheme that treats collinear, non-collinear and non-coplanar phases on equal footing. In addition to the ferromagnetic and 120° antiferromagnetic phases, we find the four-sublattice flux, the 3Q non-coplanar and the non-collinear charge-ordered states to be stable at specific values of filling fraction $n$. Inter-site Coulomb repulsion leads to intriguing spin-charge ordered phases. Most notable of these are the collinear and non-collinear magnetic states at $n=2/3$, which occur together with a pinball-liquid-like charge order. Our results demonstrate that the elementary single-orbital extended Hubbard model on a triangular lattice hosts unconventional spin-charge ordered phases, which have been reported in more complex and material-specific electronic Hamiltonians relevant to layered triangular systems.

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Kanika Pasrija, Sanjeev Kumar. 2015-11-15. Noncollinear and noncoplanar magnetic order in the extended Hubbard model on anisotropic triangular lattice. https://doi.org/10.1103/physrevb.93.195110

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