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تسجيل مستخدم جديدCurrent-induced magnetic vortex core switching in a Permalloy nanodisk
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We report on the switching of a magnetic vortex core in a sub-micron Permalloy disk, induced by a short current pulse applied in the film plane. Micromagnetic simulations including the adiabatic and non-adiabatic spin-torque terms are used to investigate the current-driven magnetization dynamics. We predict that a core reversal can be triggered by current bursts a tenth of a nanosecond long. The vortex core reversal process is found to be the same as when an external field pulse is applied. The control of a vortex cores orientation using current pulses introduces the technologically relevant possibility to address individual nanomagnets within dense arrays.
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