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Quantum model of interacting ``strings'' on the square lattice

H. Boos
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Abstract

The model which is the generalization of the one-dimensional XY-spin chain for the case of the two-dimensional square lattice is considered. The subspace of the ``string'' states is studied. The solution to the eigenvalue problem is obtained for the single ``string'' in cases of the ``string'' with fixed ends and ``string'' of types (1,1) and (1,2) living on the torus. The latter case has the features of a self-interacting system and looks not to be integrable while the previous two cases are equivalent to the free-fermion model.

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H. Boos. 1999-04-08. Quantum model of interacting ``strings'' on the square lattice. https://doi.org/10.1142/s0217751x00000069

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