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arXiv · cond-mat/0206182

Switching the magnetic configuration of a spin valve by current induced domain wall motion

Abstract

We present experimental results on the displacement of a domain wall by injection of a dc current through the wall. The samples are 1 micron wide long stripes of a CoO/Co/Cu/NiFe classical spin valve structure. The stripes have been patterned by electron beam lithography. A neck has been defined at 1/3 of the total length of the stripe and is a pinning center for the domain walls, as shown by the steps of the giant magnetoresistance curves at intermediate levels (1/3 or 2/3) between the resistances corresponding to the parallel and antiparallel configurations. We show by electric transport measurements that, once a wall is trapped, it can be moved by injecting a dc current higher than a threshold current of the order of magnitude of 10^7 A/cm^2. We discuss the different possible origins of this effect, i.e. local magnetic field created by the current and/or spin transfer from spin polarized current.

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J. Grollier, D. Lacour, V. Cros, A. Hamzic, A. Vaures, A. Fert, D. Adam, G. Faini. 2002-06-11. Switching the magnetic configuration of a spin valve by current induced domain wall motion. https://doi.org/10.1063/1.1507820

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