Thermodynamical properties of the random field Ising model

The random field Ising model is studied within the differential operator method. The phase diagrams were obtained for coordination numbers z = 4 and z = 6. They show several interesting behaviours, presenting tricritical points (only for z = 6), and re-entrant order parameters in either of the two distribution functions studied. The influence of the re-entrant behaviour on the thermodynamical properties is also investigated.