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Exact Solution of the Biquadratic Spin-1 t-J Model in One Dimension

F. C. Alcaraz·R. Z. Bariev
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Abstract

A new generalization of the t-J model with a nearest-neigbor hopping is formulated and solved exactly by the Bethe-ansatz method. The model describes the dynamics of spin-S fermions with isotropic or anisotropic interactions. In the case S=1 the magnetic interaction is biquadratic in the spin operators. In contrast to the SU(N) generalization of the t-J model, studied previously in the literature, the present model possesses beyond a massless excitation also a massive one. The physical properties indicate the existence of Cooper-type pairs with finite binding energy.

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F. C. Alcaraz, R. Z. Bariev. 1997-06-23. Exact Solution of the Biquadratic Spin-1 t-J Model in One Dimension. https://doi.org/10.1103/physrevb.56.7796

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