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Influence of anisotropic next-nearest-neighbor hopping on diagonal charge-striped phases

V. Derzhko
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Abstract

We consider the model of strongly-correlated system of electrons described by an extended Falicov-Kimball Hamiltonian where the stability of some axial and diagonal striped phases was proved. Introducing a next-nearest-neighbor hopping, small enough not to destroy the striped structure, we examine rigorously how the presence of the next-nearest-neighbor hopping anisotropy reduces the $π/2$-rotation degeneracy of the diagonal-striped phase. The effect appears to be similar to that in the case of anisotropy of the nearest-neighbor hopping: the stripes are oriented in the direction of the weaker next-nearest-neighbor hopping.

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V. Derzhko. 2005-11-22. Influence of anisotropic next-nearest-neighbor hopping on diagonal charge-striped phases. https://doi.org/10.1088/0305-4470%2F39%2F36%2F002

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