Low-temperature properties of ferromagnetic-antiferromagnetic double layer superlattices

Low-temperature magnetic properties of a Heisenberg model consisting of ferro- and antiferromagnetic layer superlattices are studied by using spin-wave theory and retarded Green's function method. The four-sublattice magnetizations and internal energy and specific heat at low temperature are calculated. The results of various physical quantities are shown for different sets of intra- and interplane coupling interactions. There is a crossover between sublattice magnetizations in each layer is affected by quantum fluctuations, thermal fluctuations and frustration of spins.