Nature of crossover from classical to Ising-like critical behavior

Abstract

We present an accurate numerical determination of the crossover from classical to Ising-like critical behavior upon approach of the critical point in three-dimensional systems. The possibility to vary the Ginzburg number in our simulations allows us to cover the entire crossover region. We employ these results to scrutinize several semi-phenomenological crossover scaling functions that are widely used for the analysis of experimental results. In addition we present strong evidence that the exponent relations do not hold between effective exponents.

4 pages RevTeX 3.0/3.1, 4 Encapsulated PostScript figures. Uses epsf.sty. Also available as PDF file at http://www.cond-mat.physik.uni-mainz.de/~luijten/erikpubs.html