Abstract

The interface magnetism between Co2FeGe Heusler alloy layers and MgO layers was investigated using 57Fe Mössbauer spectroscopy. Interface-sensitive samples, where the 57Fe isotope was used only for the interfacial atomic layer of the Co2FeGe layer on the MgO layer, were prepared using atomically controlled alternate deposition. The 57Fe Mössbauer spectra of the interface-sensitive samples at room temperature were found similar to those of the bulk-sensitive Co2FeGe films in which the 57Fe isotope was distributed throughout the films. On the other hand, the tunnel magnetoresistance effect of magnetic tunnel junctions with Co2FeGe layers as the ferromagnetic electrodes showed strong reduction at room temperature. These results indicate that the strong temperature dependence of the tunneling magnetoresistance of magnetic tunnel junctions using Heusler alloy electrodes cannot be attributed simply to the reduction of the magnetization at the interfaces between the Heusler alloy and insulator layers.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call