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تسجيل مستخدم جديدSpin-orbit torque-driven magnetization switching and thermal effects studied in TaCoFeBMgO nanowires
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R. Lo Conte
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We demonstrate magnetization switching in out-of-plane magnetized TaCoFeBMgO nanowires by current pulse injection along the nanowires, both with and without a constant and uniform magnetic field collinear to the current direction. We deduce that an effective torque arising from spin-orbit effects in the multilayer drives the switching mechanism. While the generation of a component of the magnetization along the current direction is crucial for the switching to occur, we observe that even without a longitudinal field thermally generated magnetization fluctuations can lead to switching. Analysis using a generalized Neel-Brown model enables key parameters of the thermally induced spin-orbit torques switching process to be estimated, such as the attempt frequency and the effective energy barrier.
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