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arXiv · 0705.3941

Kinetic ferromagnetism on a kagome lattice

F. Pollmann·P. Fulde·K. Shtengel
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Abstract

We study strongly correlated electrons on a kagome lattice at 1/6 and 1/3 filling. They are described by an extended Hubbard Hamiltonian. We are concerned with the limit |t|<<V<<U with hopping amplitude t, nearest-neighbor repulsion V and on-site repulsion U. We derive an effective Hamiltonian and show, with the help of the Perron-Frobenius theorem, that the system is ferromagnetic at low temperatures. The robustness of ferromagnetism is discussed and extensions to other lattices are indicated.

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F. Pollmann, P. Fulde, K. Shtengel. 2008-02-20. Kinetic ferromagnetism on a kagome lattice. https://doi.org/10.1103/physrevlett.100.136404

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