Spin momentum transfer in a nanomagnetic device with perpendicular magnetic anisotropy for both free and fixed magnetic layers is studied. The perpendicular anisotropy is induced by using CoFePt multilayer. The magnetoresistive loop shows that the perpendicular switching fields for the free and fixed layers are 170 and 380 Oe, respectively, with ΔRR=0.47%. Resistance-current scanning clearly shows a full out-of-plane switching of the free layer magnetization under a sweeping current, which fully excludes the effect of switching by the magnetic field generated by the current. The critical current density is around 1.0× 108 A cm2, which could be tuned by changing the CoFePt multilayer structures.
Bibliographical noteFunding Information:
This work was supported in part by the MRSEC Program of the National Science Foundation under Award No. DMR-0212302 and Heraeus Inc. The authors thank the discussion with Professor Jack H Judy at University of Minnesota.
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