Non-linear control of magnon-polariton hybridisation

Yamamoto, Kei; Kurebayashi, Hidekazu*

no journal, , 

Tunnel magnetoresistance in the ultrathin MnGa-based perpendicular MTJs with bcc-Co based interlayers

Suzuki, Kazuya; Ichinose, Tomohiro*; Iihama, Satoshi*; Momma, Ren*; Kamata, Naoki*; Mizukami, Shigemi*

no journal, , 

Perpendicular magnetic tunnel junctions (p-MTJs) are key devices for rich applications such as magneto-resistive random access memory, magnetic sensor, and high frequency devices. Not only do they be required to have proper magnetic properties for the applications, but they also need to have a high TMR ratio at operating temperatures. Tetragonal Mn-based alloys are one of distinctive and attractive perpendicular magnetic materials as the electrode materials for p-MTJs because of their small saturation magnetization, large coercivity, large perpendicular magnetic anisotropy, and small Gilbert damping factor. However, the p-MTJs utilizing Mn-based alloy as the ferromagnetic electrode have only exhibited small TMR at room temperature, still maximum of 60% even if FeCo interlayers were used. We have recently focused on bcc-Co based alloys as the interlayer material for MnGa-based MTJs in order to enhance further TMR. In this presentation, we demonstrate the p-MTJs utilizing bcc-CoMn interlayers and their TMR properties, and we briefly introduce recent progress for MnGa-based p-MTJs, as well.