Phase diagrams and magnetic properties of Ising thin film. Part I: Re-entrant phenomena in an amorphous thin film

An amorphous Ising film is investigated by the use of an effective field theory. The phase diagrams in (T, δ) plane, are studied for some values of n (number of layers). We found that the transition temperature of the film decreases when the disorder parameter δ increases. The re-entrant phenomena are observed for δ>1 and n≤6. Magnetization curves of the system are studied in some regions of δ where these phenomena are manifested. The first-order transitions have been observed for n≤4 and δ>1.