Magnetic properties of a diluted transverse spin- Ising film

The layer longitudinal magnetizations, their average, and both the longitudinal and the transverse susceptibilities of a diluted transverse spin- Ising film are studied within the framework of the effective field theory. The results show that the surface layer longitudinal magnetization can be smaller or larger than the internal layer longitudinal magnetization, depending on the values of the ratio of the surface exchange interactions to the bulk ones R=Js/J, the concentration c of the magnetic atoms and the temperature T/J. It is also shown that the longitudinal susceptibility diverges at the critical temperature Tc/J while the transverse susceptibility displays a cusp at the critical temperature.