The phase diagrams of a ferromagnetic thin film in a random magnetic field

•Phase diagrams of a ferromagnetic thin film are examined by the Monte Carlo simulation.•The effect of the random magnetic field on the magnetic properties is studied.•Different types of the phase diagrams are obtained.•The dependence of the magnetization and susceptibility on the temperature are investigated.

In this paper, the magnetic properties and the phase diagrams of a ferromagnetic thin film with a thickness N in a random magnetic field (RMF) are investigated by using the Monte Carlo simulation technique based on the Metropolis algorithm. The effects of the RMF and the surface exchange interaction on the critical behavior are studied. A variety of multicritical points such as tricritical points, isolated critical points, and triple points are obtained. It is also found that the double reentrant phenomenon can appear for appropriate values of the system parameters.