The Mn3Ga 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 Mn1.63Ga and MgO is of particular interest because of its spin polarization properties in tunneling junctions. We performed a chemical characterization of the MgO/Mn1.63Ga 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.
@article{arxiv.1403.3556,
title = {Investigation on Mn$_{3-\delta}$Ga/MgO interface for magnetic tunneling junctions},
author = {C. E. ViolBarbosa and S. Ouardi and T. Kubota and S. Mizukami and G. H. Fecher and T. Miyazaki and X. Kozina and E. Ikenaga and C. Felser},
journal= {arXiv preprint arXiv:1403.3556},
year = {2014}
}