2003/12/31 by M. Covington, M. AlHajDarwish, Yi Ding +5 · 3 citations
Engineering · Physics and Astronomy · #Advanced Memory and Neural Computing #Antiparallel (mathematics) #Condensed matter physics #Ferroelectric and Negative Capacitance Devices #Geometry #Giant magnetoresistance #Magnetic field #Magnetic properties of thin films #Magnetization #Magnetization dynamics #Magnetoresistance #Noise (video) #Perpendicular #Physics #Quantum mechanics #Spin (aerodynamics) #Spin valve #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.69.184406
21 pages, 7 figures, minor revisions in response to Phys. Rev. B referees
arxiv created 2004/03/30 · openalex publication_date 2004/05/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We observe magnetization dynamics induced by spin momentum transfer in the noise spectra of current perpendicular to the plane giant magnetoresistance spin valves. The dynamics are observable only for those combinations of current direction and magnetic configuration in which spin transfer acts to reorient the free layer magnetization away from the direction set by the net magnetic field. Detailed measurements as a function of magnetic configuration reveal an evolution of the noise spectra, going from a spectrum with a well-defined noise peak when the free layer is roughly collinear with the pinned layer to a spectrum dominated by 1/f noise when the free layer is in an orthogonal configuration. Finally, the amplitude of the corresponding resistance noise increases rapidly with increasing current until it saturates at a value that is a substantial fraction of the magnetoresistance between parallel and antiparallel states.