Tunnel Magneto-Resistance of Double-Barrier Magnetic Tunnel Junctions with a Central Ferrimagnet Layer Including Spin–Orbit Coupling

Tunnel magneto-resistance (TMR) ratio is studied in double-barrier magnetic tunnel junctions with a central ferrimagnet layer (DBMTJs-FI). The effects of spin–orbit coupling (SOC) within the FI layer on the TMR ratio are also taken into account. A tight-binding model is applied to compute transmission function by the nonequilibrium Green’s function method. A higher TMR ratio is found for the DBMTJs-FI compared to that for the DBMTJs with a central ferromagnet layer (DBMTJs-F) in the absence of the SOC. Therefore, a novel application for the FIs is presented by these findings in the field of spintronics.