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Magnetic and Charge Correlations of the 2-dimensional $t-t'-U$ Hubbard model

Raymond Frésard·Walter Zimmermann
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Abstract

Using a spin-rotation invariant six-slave boson representation, we study the square lattice Hubbard model with nearest-neighbor hopping $t$ and next-nearest neighbor hopping $t'$. We discuss the influence of $t'$ on the charge and magnetic properties. In the hole-doped domain, we find that a negative $t'$ strongly favors itinerant ferromagnetism over any incommensurate phase, especially in the strong coupling regime. For positive $t'$ magnetic fluctuations are suppressed. A tight connection between frustrated charge dynamics and large magnetic fluctuations is pointed out. A clear tendency towards striped charge ordering is found in the regime of large positive $t'$.

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Raymond Frésard, Walter Zimmermann. 1998-12-15. Magnetic and Charge Correlations of the 2-dimensional $t-t'-U$ Hubbard model. https://doi.org/10.1103/physrevb.58.15288

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