Finite size effects on the exchange bias properties of ferromagnetic/antiferromagnetic bilayers

Exchange bias (EB) refers to the shift of the hysteresis loop, typically observed in exchange interacting ferromagnetic (FM)-antiferromagnetic (AFM) materials. During the last decades, EB properties have been extensively investigated, mainly in thin films, due to their technological applications in magnetic random access memories and magnetoresistive read heads based on spin valves or tunnel junctions. Recently, the drastic increase in the areal density of magnetic recording media has motivated the study of EB properties in systems of reduced lateral dimensions. The reduction of the lateral dimensions of an EB system down to length scales comparable to the FM or to the AFM magnetic domain sizes is also interesting from a fundamental point of view since this results in a confinement and subsequent alteration of the FM and AFM domain structures, hence allowing to probe the role of domains on EB.