Marshall-Peierls Sign Rule in Frustrated Heisenberg Chains

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. PACS numbers: 75.10.Jm, 75.40.Mg, 75.50.Ee