ABSTRACT
In this chapter, the author shows the effects of frustration in an antiferromagnetic film of face-centered cubic (FCC) lattice with Heisenberg spin model including an Ising-like anisotropy. He shows that presence of the surface reduces the ground state (GS) degeneracy found in the bulk. The author also uses the Green’s function (GF) method for quantum counterpart model. He shows the effect of the presence of a film surface in a system which is known to be very frustrated, namely the FCC antiferromagnet. From the renormalization group calculations, since anisotropy is a relevant parameter, one expects that any finite anisotropy will lead to Ising-like critical behavior, but with corrections due to the continuous nature of Heisenberg spins before one enters the linear regime around the Ising fixed point. In addition, it is better than the spin wave theory at higher temperatures and can be used up to the transition temperature with of course less precision on the nature of phase transition.
