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Formation of clusters in the two dimensional t-J model: The mechanism for phase separation

A. Fledderjohann·A. Langari·K. -H. Muetter
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Abstract

The emergence of phase separation is investigated in the framework of a 2D t-J model by means of a variational product ansatz, which covers the infinite lattice by two types of L x L clusters. Clusters of the first type are completely occupied with electrons, i.e. they carry maximal charge Q_e=L^2 and total spin 0, and thereby form the antiferromagnetic background. Holes occur in the second type of clusters -- called ``hole clusters''. They carry a charge Q_h 0.5) it turns out that hole clusters are occupied with an even number Q_h<L^2 of electrons and carry a total spin 0. For increasing αthe charge Q_h(α) of the hole clusters decreases.Some points on the boundary curve can be extracted from Q_h(α).

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A. Fledderjohann, A. Langari, K. -H. Muetter. 2006-05-09. Formation of clusters in the two dimensional t-J model: The mechanism for phase separation. https://doi.org/10.1088/0953-8984%2F18%2F20%2F017

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