arXiv:cond-mat/0003207 · Acta Physica Polonica A
Marshall-Peierls Sign Rule in Frustrated Heisenberg Chains
A. Voigt, Johannes Richter
Abstract
We consider the frustrated antiferromagnetic S = 1 Heisenberg quantum spin chain with regard to the Marshall-Peierls sign rule.Using exact diagonalization data we investigate the breakdown of the Marshall-Peierls sign rule in dependence on frustration and compare our findings with data for s = 1/2.We calculate a critical value of frustration J21" , where the Marshall-Peierls sign rule is violated.The extrapolation of this value to the infinite chain limit holds J?' s: 0.016, lower than in the case of s = 1/2 (J2crit 0.027).This points to a stronger influence of frustration in the case of s = 1.Nevertheless, the calculation of the weight of the Ising-states violating the Marshall-Peierls sign rule shows that the latter holds approximately even for a quite large frustration and may be used for numerical techniques.