Influence of interfacial roughness on exchange bias in core-shell nanoparticles

Abstract

[EN]Exchange bias is a phenomenon that has attracted a great deal of interest in the 50 years following its discovery, but that is still lacking a deep theoretical understanding of its origin in core-shell nanoparticles. We present calculations of ferro-antiferromagnetic core-shell nanoparticles with roughened interfaces and demonstrate a wide dispersion in the calculated exchange-bias field caused by the roughening. Furthermore, we show that the magnitude of the exchange-bias field is strongly correlated with the net interfacial moment in the antiferromagnet, proportional to the degree of the interfacial roughness. This provides new insight into the origins of exchange bias in core-shell nanoparticles