Characterization and analysis of the training effect of exchange bias in coupled NiFe/IrMn bilayers

摘要

The training effect of the so-called exchange bias in coupled polycrystalline NiFe/IrMn thin films has been experimentally and theoretically investigated. A different formula is used to describe the exchange bias dependence on the measurement cycle number. It can be understood to be a consequence of the antiferromagnetic domain dynamics based on the Kolmogorov-Avrami [Izv. Akad. Nauk, Sen Math. 3, 355 (1937); J. Chem. Phys. 8, 212 (1940)] model, which describes the nucleation and growth of antiferromagnetic domains in the film structures.