Magnetic properties in the Ising-mixed spin- -spin-1 superlattice

An expanded Bethe–Peierls approximation is used to study the magnetic properties of the magnetic superlattice, which consists of a mixed spin- and spin-1 (with a single-ion anisotropy D) alternate ferromagnetic monolayers with antiferromagntic coupling at the interlayers. By using the transfer matrix method, we calculate the magnetization and the initial susceptibility as functions of temperature for different interlayer coupling, single-ion anisotropy and the relative intralayer interaction. We summarize the behaviors of the temperature dependence of the layered magnetizations, total magnetization and the initial susceptibility, and explain the reason that two peaks appears in the initial susceptibility curve in some parameter range.