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arXiv · 1901.02054

Competing Charge and Magnetic Order in Fermionic Multi-Component Systems

Mohsen Hafez-Torbati·Walter Hofstetter
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Abstract

We consider the fermionic SU($3$) Hubbard model on the triangular lattice in the presence of a three-sublattice staggered potential which provides the possibility to investigate the competition of charge and magnetic order in three-component systems. We show that depending on the strength of the staggered potential $Δ$, the Hubbard interaction $U$ destabilizes the band insulator (BI) at small $U$ into the Mott insulator (MI) at large $U$ in three different ways with different intermediate phases. This leads to a rich phase diagram in the $U$-$Δ$ plane. Our results indicate that multi-component systems show not only exotic states in the Mott regime as has been considered previously, but also interesting competition between charge and magnetic orders.

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Mohsen Hafez-Torbati, Walter Hofstetter. 2019-07-26. Competing Charge and Magnetic Order in Fermionic Multi-Component Systems. https://doi.org/10.1103/physrevb.100.035133

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