The spin- Ising film with surface defects

Abstract: Using Monte Carlo simulations, we have studied the influence of surface defects on the critical behavior of magnetic spin- Ising film on a cubic lattice structure. We derive the phase diagram and the critical exponent β in the case of a perfect surface. In such films, the critical temperature can shift to either lower or higher values compared to the corresponding bulk one. In the case of a surface with random, ‘weak’ or ‘strong’ interactions between neighboring spins, it is found that the critical exponent β 1 follows very closely that of the perfect surface case. Far from the critical temperature, the effective exponent decreases with increasing the concentration of strong interactions p. [Copyright &y& Elsevier]