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A generalized spin ladder in a magnetic field

Holger Frahm·Claus Rödenbeck
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Abstract

We study the phase diagram of coupled spin-1/2 chains with bilinear and (chiral) three-spin exchange interactions in a magnetic field. The model is soluble on a one-parametric line in the space of coupling constants connecting the limiting cases of a single and two decoupled Heisenberg chains with nearest neighbour exchange only. We give a complete classification of the low-energy properties of the integrable system and introduce a numerical method which allows to study the possible phases of spin ladder systems away from the soluble line in a magnetic field.

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Holger Frahm, Claus Rödenbeck. 1998-12-07. A generalized spin ladder in a magnetic field. https://doi.org/10.1007/s100510050870

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