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arXiv · 0706.4423

Tuning Kinetic Magnetism of Strongly Correlated Electrons via Staggered Flux

Yi-Fei Wang·Chang-De Gong·Z. D. Wang
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Abstract

We explore the kinetic magnetism of the infinite-$U$ repulsive Hubbard models at low hole densities on various lattices with nearest-neighbor hopping integrals modulated by a staggered magnetic flux $\pmϕ$. Tuning $ϕ$ from 0 to $π$ makes the ground state (GS) change from a Nagaoka-type ferromagnetic state to a Haerter-Shastry-type antiferromagnetic state at a critical $ϕ_c$, with both states being of kinetic origin. Intra-plaquette spin correlation, as well as the GS energy, signals such a quantum criticality. This tunable kinetic magnetism is generic, and appears in chains, ladders and two-dimensional lattices with squares or triangles as elementary constituents.

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Yi-Fei Wang, Chang-De Gong, Z. D. Wang. 2007-06-29. Tuning Kinetic Magnetism of Strongly Correlated Electrons via Staggered Flux. https://doi.org/10.1103/physrevlett.100.037202

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