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Ground state properties of two spin models with exactly known ground states on the square lattice

A. Sindermann·U. Löw·J. Zittartz
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Abstract

We introduce a new two-dimensional model with diagonal four spin exchange and an exactly knownground-state. Using variational ansaetze and exact diagonalisation we calculate upper and lower bounds for the critical coupling of the model. Both for this model and for the Shastry-Sutherland model we study periodic systems up to system size 6x6.

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A. Sindermann, U. Löw, J. Zittartz. 2006-05-18. Ground state properties of two spin models with exactly known ground states on the square lattice. https://doi.org/10.1142/s0129183106009709

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