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arXiv · 1809.07996

Exchange Bias in the [CoO/Co/Pd]10 Antidot Large Area Arrays

Abstract

Magnetic nanostructures revealing exchange bias effect have gained a lot of interest in recent years due to their possible applications in modern devices with various functionalities. In this paper, we present our studies on patterned [CoO/Co/Pd]10 multilayer where ferromagnetic material is in a form of clusters, instead of being a continuous layer. The system was patterned using nanosphere lithography technique which resulted in creation of an assembly of well-ordered antidots or islands over a large substrate area. We found that the overall hysteresis loop of the films consists of hard and soft components. The hard component hysteresis loop exhibits a large exchange bias field up to -11 kOe. The patterning process causes a slight increase of the exchange field as the antidot radius rises. We also found that the material on edges of the structures gives rise to a soft unbiased magnetization component.

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Marcin Perzanowski, Michal Krupinski, Arkadiusz Zarzycki, Andrzej Dziedzic, Yevhen Zabila, Marta Marszalek. 2018-09-21. Exchange Bias in the [CoO/Co/Pd]10 Antidot Large Area Arrays. https://doi.org/10.1021/acsami.7b07665

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