Critical behavior of magnetic thin films

We study the critical behavior of magnetic thin films as a function of the film thickness. We use the ferromagnetic Ising model with the high-resolution multiple histogram Monte Carlo (MC) Simulation. We show that though the 2D behavior remains dominant at small thicknesses, there is a systematic Continuous deviation of the critical exponents from their 2D values. We explain these deviations using the concept of "effective" exponents Suggested by Capehart and Fisher in a finite size analysis. The shift of the critical temperature with the film thickness obtained here by MC simulation is in an excel lent agreement with their prediction. (C) 2008 Elsevier B.V. All rights reserved.