Meron-cluster algorithms and chiral-symmetry breaking in a (2+1)D staggered fermion model

The recently developed meron-cluster algorithm completely solves the exponentially difficult sign problem for a number of models previously inaccessible to numerical simulation. We use this algorithm in a high-precision study of a model of N = 1 flavor of staggered fermions in (2 + 1) dimensions with a four-fermion interaction. This model cannot be explored using standard algorithms. We find that the 2(2) chiral symmetry of this model is spontaneously broken at low temperatures and that the finite-temperature chiral phase transition is in the universality class of the 2D Ising model, as expected. (C) 2000 Elsevier Science B.V. All rights reserved.