AVS 47th International Symposium
    Magnetic Interfaces and Nanostructures Thursday Sessions
       Session MI+NS+NANO 6-ThM

Paper MI+NS+NANO 6-ThM8
Current-driven Magnetization Reversal in Nanopillars

Thursday, October 5, 2000, 10:40 am, Room 206

Session: Nanomagnetism
Presenter: F.J. Albert, Cornell University
Authors: F.J. Albert, Cornell University
J.A. Katine, IBM Almaden
R.A. Buhrman, Cornell University
R.H. Koch, IBM Research Division
E.B. Myers, Cornell University
D.C. Ralph, Cornell University
Correspondent: Click to Email
As reported elsewhere, we have successfully fabricated functional F/N/F thin film nanopillar devices with lateral dimensions down to 60 nm, and with one ferromagnetic layer considerably thicker (magnetically harder) than the other. A substantial shape anisotropy has been introduced by patterning a 2 to 1 aspect ratio into these nanopillars. This shape anisotropy is confirmed with the behavior of the measured switching field as a function of angle to the elongated axis. The resistance of these devices shows abrupt, single-domain-like switching when the spin-polarized current flowing through the nanopillar exceeds a critical value and forces the two F layers either into parallel or anti-parallel alignment, depending on the current direction. Here we will report on the results of detailed studies of this spin-transfer switching effect as a function of magnetic field, magnetic orientation and nanopillar composition. Also we will report on the spin-transfer switching dynamics of these devices, measured by probing them with extremely short pulses of current. We are also pursuing the thickness dependence of the switching behavior and will report these results.