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arXiv · 1603.09618

Coercivity and random interfacial exchange coupling in CoPt/Co films

V. Alexandrakis·D. Kechrakos·N. Moutis·D. Niarchos·G. Hadjipanayis·I. Panagiotopoulos
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Abstract

Hard-soft bilayers are analogous to prototype exchange-biased ferromagnetic -antiferromagnetic systems as the minor loop of the soft layer is biased by the hard and furthermore they offer bias layer tunability. In sputtered CoPt/Co hard-soft bilayers we demonstrate that the exchange bias field shows a linear dependence on the hard layer magnetization, while the coercivity shows a quadratic dependence. Analysis of the minor hysteresis loop features supported by Monte-Carlo simulations provide clear evidence that the coercivity of the soft layer is mainly determined by the tunable randomness of the domain state of the hard layer.

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V. Alexandrakis, D. Kechrakos, N. Moutis, D. Niarchos, G. Hadjipanayis, I. Panagiotopoulos. 2016-03-31. Coercivity and random interfacial exchange coupling in CoPt/Co films. https://doi.org/10.1063/1.4945027

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