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Role of structural defects on exchange bias in the epitaxial CoO/Co system

M. R . Ghadimi·B. Beschoten·G. Güntherodt
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Abstract

We have studied the influence of non-magnetic defects throughout the antiferromagnet Co_{1-y}O on the exchange bias (EB) in epitaxially grown Co_{1-y}O/Co bilayers. These defects are either substitutional or structural (twin boundaries and surface morphology) which both lead to an increase of the EB-field. We find a dominance of twin boundaries over surface morphology (roughness) in enhancing EB which is consistent with the domain state model for exchange bias. In contrast, the crystal orientation of the Co_{1-y}O layer does not show a significant effect on the EB in this system.

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M. R . Ghadimi, B. Beschoten, G. Güntherodt. 2005-08-31. Role of structural defects on exchange bias in the epitaxial CoO/Co system. https://doi.org/10.1063/1.2152111

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