Magnetic stability in exchange-spring and exchange-bias systems after multiple switching cycles

We have studied the magnetic stability in exchange-bias and exchange-spring systems during repeated reversal of the pinned layer. The samples were prepared by epitaxial sputter deposition. The exchange-biased system consists of a combination of ferromagnetic and antiferromagnetic Fe/Cr superlattices. The exchange-spring system is a bilayer structure made of hard Sm-Co and soft Fe ferromagnetic layers. The magnetic properties were investigated using the magneto-optic Kerr effect during repeated reversal of the soft layer magnetization by field cycling up to 10(7) times. The experimentally observed decay behaviors are discussed in terms of microstructure and spin configuration of the pinning layers. (C) 2001 American Institute of Physics.