Spin-transfer magnetic random access memory devices with an orthogonal polarizing layer

Abstract

Spin-transfer magnetic random access memory (MRAM) devices with a polarizing layer magnetized perpendicular to the free and the reference layers are believed to improve the writing performance by inducing a large spin-transfer torque on the free layer at the beginning of the switching process. Experimental realizations of such devices, both with all-metal structures and magnetic tunnel junctions have been made. Faster switching with less energy cost in the orthogonal devices has been achieved comparing to their collinear counterparts. In addition, the processional switching process in such devices has been demonstrated in both statistical and time-resolved measurements. Although further theoretical and material studies are needed for thorough understanding of the switching process and improving the device performance, the orthogonal MRAM devices hold great potential for memory applications operating at low temperatures as well as those that require fast writing speed.