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Exactly solvable two-dimensional quantum spin models

D. V. Dmitriev·V. Ya. Krivnov·A. A. Ovchinnikov
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Abstract

A method is proposed for constructing an exact ground-state wave function of a two-dimensional model with spin 1/2. The basis of the method is to represent the wave function by a product of fourth-rank spinors associated with the sites of a lattice and the metric spinors corresponding to bonds between nearest neighbor sites. The function so constructed is an exact wave function of a 14-parameter model. The special case of this model depending on one parameter is analyzed in detail. The ground state is always a nondegenerate singlet, and the spin correlation functions decay exponentially with distance. The method can be generalized for models with spin 1/2 to other types of lattices.

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D. V. Dmitriev, V. Ya. Krivnov, A. A. Ovchinnikov. 1999-11-24. Exactly solvable two-dimensional quantum spin models. https://doi.org/10.1134/1.558776

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