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arXiv · 1708.08516

Dependence of Dzyaloshinskii-Moriya interaction on the oxygen coverage in Pt/Co/MOx trilayers

Dayane de Souza Chaves·Fernando Ajejas·Viola Krizakova·Jan Vogel·Stefania Pizzini
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Abstract

We have studied the interfacial Dzyaloshinskii-Moriya interaction (DMI) in a series of Pt/Co/MOx (M=Al, Gd) trilayers in which the degree of oxidation of the top Co interface is varied. To access to reliable values of the DMI strength, we have used a method based on the measurement of the saturation velocity of field driven chiral Néel domain walls. We show that the effective DMI strength in the Pt/Co/MOx trilayers varies with the oxidation degree of the Co/MOx interface. This strongly suggests that the Co/MOx interface gives a distinct contribution to the total DMI, adding to that of the Pt/Co interface. The DMI presents a maximum for the oxygen coverage maximizing also the interface magnetic anisotropy energy Ks. This calls for common microscopic origins for the contributions of the Co/MOx interface to DMI and Ks.

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Dayane de Souza Chaves, Fernando Ajejas, Viola Krizakova, Jan Vogel, Stefania Pizzini. 2017-08-28. Dependence of Dzyaloshinskii-Moriya interaction on the oxygen coverage in Pt/Co/MOx trilayers. https://doi.org/10.1103/physrevb.99.144404

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