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Generalised Shastry-Sutherland Models in three and higher dimensions

Naveen Surendran·R. Shankar
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Abstract

We construct Heisenberg anti-ferromagnetic models in arbitrary dimensions that have isotropic valence bond crystals (VBC) as their exact ground states. The d=2 model is the Shastry-Sutherland model. In the 3-d case we show that it is possible to have a lattice structure, analogous to that of SrCu_2(BO_3)_2, where the stronger bonds are associated with shorter bond lengths. A dimer mean field theory becomes exact at d -> infinity and a systematic 1/d expansion can be developed about it. We study the Neel-VBC transition at large d and find that the transition is first order in even but second order in odd dimensions.

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Naveen Surendran, R. Shankar. 2002-12-27. Generalised Shastry-Sutherland Models in three and higher dimensions. https://doi.org/10.1103/physrevb.66.024415

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