The transverse spin-1 Ising film

Within the framework of the effective-field theory, we examine the phase tr ansitions of a transverse spin-1 Ising film. We discuss an L-layer film of simple cubic symmetry with nearest-neighbour exchange interactions in which the exchange interaction strengths in surface layers are assumed to be dif ferent from the bulk values, and we derive and illustrate expressions for t he phase diagrams and order parameter profiles. It is found that for a rati o of the surface exchange interactions to the bulk ones R = J(s)/J less tha n a critical value R-c, the critical temperature T-c/J of the film is small er than the bulk critical temperature T-c(B)/J and, as L is increased furth er, T-c/J increases. However, for R > R-c, T-c/J is greater than the bulk c ritical temperature T-c(B)/J and, as L is increased further, T-c/J decrease s.