Spin-transfer switching in MgO-based magnetic tunnel junctions

We present spin-transfer switching results for MgO-based magnetic tunneling junctions (MTJs) with large tunneling magnetoresistance ratio of up to 150% and low intrinsic switching current density (Jc0) of (2–3)×106A∕cm2. The low intrinsic switching current density is attributed to high tunneling spin polarization (TSP) in MgO-based MTJs. The current switching data are discussed based on a qualitative study of TSP in MgO-based MTJs. Additional film stack modification needed to decrease the switching current to meet the requirement of advanced magnetoresistive random access memory application is also discussed.

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