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arXiv · hep-th/9912252

Ground State of the Quantum Symmetric Finite Size XXZ Spin Chain with Anisotropy Parameter $Δ= {1/2}$

V. Fridkin·Yu. Stroganov·D. Zagier
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Abstract

We find an analytic solution of the Bethe Ansatz equations (BAE) for the special case of a finite XXZ spin chain with free boundary conditions and with a complex surface field which provides for $U_q(sl(2))$ symmetry of the Hamiltonian. More precisely, we find one nontrivial solution, corresponding to the ground state of the system with anisotropy parameter $Δ= {1/2}$ corresponding to $q^3 = -1$.

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V. Fridkin, Yu. Stroganov, D. Zagier. 1999-12-27. Ground State of the Quantum Symmetric Finite Size XXZ Spin Chain with Anisotropy Parameter $Δ= {1/2}$. https://doi.org/10.1088/0305-4470%2F33%2F13%2F101

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