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arXiv · 1003.2478

Exchange bias and interface electronic structure in Ni/Co3O4(011)

C. A. F. Vaz·E. I. Altman·V. E. Henrich
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Abstract

A detailed study of the exchange bias effect and the interfacial electronic structure in Ni/Co3O4(011) is reported. Large exchange anisotropies are observed at low temperatures, and the exchange bias effect persists to temperatures well above the Neel temperature of bulk Co3O4, of about 40 K: to ~80 K for Ni films deposited on well ordered oxide surfaces, and ~150 K for Ni films deposited on rougher Co3O4 surfaces. Photoelectron spectroscopy measurements as a function of Ni thickness show that Co reduction and Ni oxidation occur over an extended interfacial region. We conclude that the exchange bias observed in Ni/Co3O4, and in similar ferromagnetic metallic/Co3O4 systems, is not intrinsic to Co3O4 but rather due to the formation of CoO at the interface.

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C. A. F. Vaz, E. I. Altman, V. E. Henrich. 2010-03-12. Exchange bias and interface electronic structure in Ni/Co3O4(011). https://doi.org/10.1103/physrevb.81.104428

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