Polycrystalline exchange-biased bilayers: Magnetically effective versus structural antiferromagnetic grain volume distribution

The magnetic characteristics of polycrystalline exchange-biased antiferromagnet/ferromagnet-bilayers are determined by a complex interplay parameters, describing structural and properties the material system, including in particular grain volume distribution antiferromagnet. An ideal characterization such systems would be non-destructive determination relevant parameters for each individual grain. This is most cases not feasible, since typical methods do average over larger areas. Here, we show that it however possible to determine averaged microscopic from macroscopic quantities measured vectorial Kerr magnetometry comparison an elaborate model. In particular, estimate magnetically effective antiferromagnetic size distribution, being essential interface exchange coupling ferromagnetic layer. We found active sizes differs one, indicating order, bias, extends only part grains' volumes.