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Solution of a two leg spin ladder system

Jon Links·Angela Foerster
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Abstract

A new model for a spin 1/2 ladder system with two legs is introduced. It is demonstrated that this model is solvable via the Bethe ansatz method for arbitrary values of the rung coupling J. This is achieved by a suitable mapping from the Hubbard model with appropriate twisted boundary conditions. We determine that a phase transition between gapped and gapless spin excitations occurs at the critical value J_c=1/2 of the rung coupling.

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Jon Links, Angela Foerster. 1999-11-06. Solution of a two leg spin ladder system. https://doi.org/10.1103/physrevb.62.65

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