Magnetic hysteresis loop in antiferromagnetically coupled bilayer structures

作者:Ma Yan; Du An*
来源:Physica Status Solidi B-Basic Solid State Physics, 2008, 245(4): 740-744.
DOI:10.1002/pssb.200743173

摘要

The hysteresis behavior of a bilayer film system, in which a hard ferromagnetic layer with larger anisotropy and spin-3/2 couples with a soft ferromagnetic layer with smaller anisotropy and spin-1 antiferromagnetically, is studied by using the Ising model and the linear cluster approach. We calculate the magnetic reversal of the soft magnetic layer at low field while keeping the saturated magnetization state of the hard magnetic layer unperturbed, and find a phenomenon of exchange bias. The influences of anisotropy, intralayer exchange in the soft magnetic layer, and the interlayer exchange on the coercivity and exchange bias in the bilayer film are discussed. It is found that increasing the interlayer coupling can enhance the exchange bias of the system, and the easy plane anisotropy in soft magnetic layers can induce the hysteresis loop moving towards positive field.