UvA - DARE ( Digital Academic Repository ) Fine structure of the Bethe Ansatz for the spin - 1 / 2 Heisenberg XXX model
نویسنده
چکیده
We analyse the Bethe ansalz equations for the two-particle sector of the spin-; Heisenberg X X X model on a one-dimensional lattice of length N . We show that. beginning at a critical lattice length of N = 21.86. new pairs of real solutions develop, whereas complex solutions star1 to disappear. 'Ibe integers (that appear in the logarithmic form of the Bethe equations) of the o w solutions do not fit inlo the conventional classification scheme. The total number of solutions in the two-particle sector remains unchanged and is i n agreement with the claim that the SU(2) extended Bethe ansatz gives a complete set of ZN eigenstates.
منابع مشابه
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On the Algebraic Bethe Ansatz for XXX spin chain: creation operators " beyond the equator ". Abstract Considering the XXX spin-1/2 chain in the framework of the Algebraic Bethe Ansatz (ABA) we make the following short comment: the product of the creation operators corresponding to the recently found solution of the Bethe equations " on the wrong side of the equator " [1] is just zero (not only ...
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