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تسجيل مستخدم جديدReduction of threshold current density for current-driven domain wall motion by shape control
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We investigated the aspect ratio (thickness/width) dependence of the threshold current density required for the current-driven domain wall (DW) motion for the Ni81Fe19 nanowires. It has been shown theoretically that the threshold current density is proportional to the product of the hard-axis magnetic anisotropy Kperp and the DW width lamda. (Phys. Rev. Lett. 92, 086601 (2004).) We show experimentally that Kperp can be controlled by the magnetic shape anisotropy in the case of the Ni81Fe19 nanowires, and that the threshold current density increases with an increase of Kperp*l. We succeeded to reduce the threshold current density by half by the shape control.
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It was found that high current density needed for the current-driven domain wall motion results in the Joule heating of the sample. The sample temperature, when the current-driven domain wall motion occurred, was estimated by measuring the sample res
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