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arXiv · 1403.3556

Investigation on Mn$_{3-δ}$Ga/MgO interface for magnetic tunneling junctions

C. E. ViolBarbosa·S. Ouardi·T. Kubota·S. Mizukami·G. H. Fecher·T. Miyazaki·X. Kozina·E. Ikenaga·C. Felser
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Abstract

The Mn$_3$Ga Heusler compound and related alloys are the most promising materials for the realization of spin-transfer-torque switching in magneto tunneling junctions. Improved performance can be achieved by high quality interfaces in these multilayered structured devices. In this context, the interface between Mn$_{1.63}$Ga and MgO is of particular interest because of its spin polarization properties in tunneling junctions. We performed a chemical characterization of the MgO/Mn$_{1.63}$Ga junction by hard x-ray photoelectron spectroscopy (HAXPES). The experiment indicated the formation of Ga-O bonds at the interface and evidenced changes in the local environment of Mn atoms in the proximity of the MgO film. In addition, we show that the insertion of a metallic Mg-layer interfacing the MgO and Mn--Ga film strongly suppresses the oxidation of gallium.

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C. E. ViolBarbosa, S. Ouardi, T. Kubota, S. Mizukami, G. H. Fecher, T. Miyazaki, X. Kozina, E. Ikenaga, C. Felser. 2014-05-09. Investigation on Mn$_{3-δ}$Ga/MgO interface for magnetic tunneling junctions. https://doi.org/10.1063/1.4890582

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