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Exact solution of a spin-ladder model

Yupeng Wang
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Abstract

An integrable spin-ladder model with nearest-neighbor exchanges and biquadratic interactions is proposed. With the Bethe ansatz solutions of the model hamiltonian, it is found that there are three possible phases in the ground state, i.e., a rung-dimerized phase with a spin gap, and two massless phases. The possible fixed points of the system and the quantum critical behavior at the critical point $J=J_+^c$ are discussed.

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Yupeng Wang. 1999-01-18. Exact solution of a spin-ladder model. https://doi.org/10.1103/physrevb.60.9236

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