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Exact ground states for a class of one-dimensional frustrated quantum spin models

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

We have found the exact ground state for two frustrated quantum spin-1/2 models on a linear chain. The first model describes ferromagnet- antiferromagnet transition point. The singlet state at this point has double-spiral ordering. The second model is equivalent to special case of the spin-1/2 ladder. It has non-degenerate singlet ground state with exponentially decaying spin correlations and there is an energy gap. The exact ground state wave function of these models is presented in a special recurrent form and recurrence technics of expectation value calculations is developed.

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D. V. Dmitriev, V. Ya. Krivnov, A. A. Ovchinnikov. 1999-12-01. Exact ground states for a class of one-dimensional frustrated quantum spin models. https://doi.org/10.1103/physrevb.56.5985

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