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Spin-transfer dynamics in spin valves with out-of-plane magnetized CoNi free layers



William H. Rippard, Alina M. Deac, Matthew R. Pufall, Justin M. Shaw, Mark W. Keller, Stephen E. Russek, Gerrit E. Bauer, Claudio Serpico


We have measured spin-transfer-induced dynamics in magnetic nanocontact devices having a perpendicularly magnetized Co/Ni free layer and an in-plane magnetized CoFe fixed layer. The frequencies and powers of the excitations agree well with the predictions of the single-domain model and indicate that the excited dynamics correspond to precessional orbits with angles ranging from zero to 90° as the applied current is increased at a fixed field. From measurements of the onset current as a function of applied field strength we estimate the magnitude of the spin torque asymmetry parameter λ{approximately equal}1.5. By combining these with spin torque ferromagnetic resonance measurements, we also estimate the spin-wave radiation loss in these devices.
Physical Review B


magnetics, spin electronics, magnetodynamics, nanomagnetics


Rippard, W. , Deac, A. , Pufall, M. , Shaw, J. , Keller, M. , Russek, S. , Bauer, G. and Serpico, C. (2010), Spin-transfer dynamics in spin valves with out-of-plane magnetized CoNi free layers, Physical Review B (Accessed July 21, 2024)


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Created January 29, 2010, Updated February 19, 2017