The critical Binder cumulant in a two-dimensional Ising model with competing interactions

Selke, W. and Shchur, L.N.
Technische Hochschule Aachen, Germany
Landau-Institute for Theoretical Physics, Chernogolovka, Russia


The Binder cumulant at the phase transition of Ising models on square lattices with ferromagnetic couplings between nearest neighbors and with competing antiferromagnetic couplings between next--nearest neighbors, along only one diagonal, is determined using Monte Carlo techniques. In the phase diagram a disorder line occurs separating regions with monotonically decaying and with oscillatory spin--spin correlations. Findings on the variation of the critical cumulant with the ratio of the two interaction strengths are compared to related recent results based on renormalization group calculations.