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arXiv · 1110.5237

Spin and charge orderings in the atomic limit of the U-V-J model

Ferdinando Mancini·Evgeny Plekhanov·Gerardo Sica
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Abstract

In this paper we study a generalization of the 1D Hubbard model by considering density-density and Ising-type spin-spin nearest neighbor (NN) interactions, parameterized by $V$ and $J$, respectively. We present the T=0 phase diagram for both ferro ($J>0$) and anti-ferro ($J<0$) coupling obtained in the narrow-band limit by means of an extension to zero-temperature of the transfer-matrix method. Based on the values of the Hamiltonian parameters, we identify a number of phases that involve orderings of the double occupancy, NN density and spin correlations, being these latter very fragile.

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Ferdinando Mancini, Evgeny Plekhanov, Gerardo Sica. 2011-10-24. Spin and charge orderings in the atomic limit of the U-V-J model. https://doi.org/10.1088/1742-6596/391/1/012148

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