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Large N behavior of string solutions in the Heisenberg model

T. Fujita·T. Kobayashi·H. Takahashi
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Abstract

We investigate the large $N$ behavior of the complex solutions for the two magnon system in the S=1/2 Heisenberg XXZ model. The Bethe ansatz equations are numerically solved for the string solutions with new iteration method. A clear evidence of the violation of the string configurations is found at $N=22,62,121,200,299,417$, but the broken states are still Bethe states. The number of the Bethe states is consistent with the exact diagonalization, except one singular state.

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T. Fujita, T. Kobayashi, H. Takahashi. 2002-07-04. Large N behavior of string solutions in the Heisenberg model. https://doi.org/10.1088/0305-4470%2F36%2F6%2F302

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