Naslov
Switching a spin valve back and forth by current-induced domain wall motion

Autori
Cros, Vincent ; Grollier, Julie ; Boulenc, Pierre ; Hamzić, Amir ; Vaures, Annie ; Faini, Giancarlo ; Fert, Albert

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
9th Joint MMM/Intermag Conference, Anaheim, SAD / - , 2004

Skup
9th Joint MMM/Intermag Conference

Mjesto i datum
Anaheim (CA), Sjedinjene Američke Države, 05.01.2004. - 09.01.2004

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
spintronics; spin-injection; domain wall

Sažetak
Switching the magnetic configuration of a micro-device by spin transfer from a spin-pI:llarized current, rather than by applying an external field, is the central idea of a present extensive research. In this work, we present some experimental results concerning the current-induced displacement of a domain wall (DW) in the permalloy (Py) layer of a spin valve structure. Our samples are 300 nm wide and 20 micrometer long stripes patterned bye-beam lithography using a lift-off technique. The spin valves, deposited by sputtering, have a final structure CoO (3nm)/Co(7nm)/Cu(10nm)/Py(5nm)/Au(3nm). The top Au electrodes are processed by UV lithography. In contrast with our previous experiments, the only pinning centers for the DW in the Py soft layer are natural defects of the stripe. All the measurements were performed at room temperature. The DW position in the stripe is detected directly by GMR measurements. In zero or very low field, the DW displacement is in opposite directions for opposite dc currents and the current density required to move DW is only of the order of 10^6 A/cm^2. For H = 3 Oe, a back and forth DW motion between two stable position is observed. These results are consistent with the spin transfer mechanism introduced by Berger. Out of this low field range, the current is still able to unpin the DW, but the direction of the DW motion is now controlled by the applied field direction. This more complex and still unclear behavior was also observed in our former experiments with stronger (artificial) pinning centers, where the motion could be obtained only by combining current and applied field.

Izvorni jezik
Engleski

Znanstvena područja
Fizika

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