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تسجيل مستخدم جديدPrecession-torque-driven domain-wall motion in out-of-plane materials
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Domain-wall (DW) motion in magnetic nanostrips is intensively studied, in particular because of the possible applications in data storage. In this work, we will investigate a novel method of DW motion using magnetic field pulses, with the precession torque as the driving mechanism. We use a one dimensional (1D) model to show that it is possible to drive DWs in out-of-plane materials using the precession torque, and we identify the key parameters that influence this motion. Because the DW moves back to its initial position at the end of the field pulse, thereby severely complicating direct detection of the DW motion, depinning experiments are used to indirectly observe the effect of the precession torque. The 1D model is extended to include an energy landscape in order to predict the influence of the precession torque in the depinning experiments. Although preliminary experiments did not yet show an effect of the precession torque, our calculations indicate that depinning experiments can be used to demonstrate this novel method of DW motion in out-of-plane materials, which even allows for coherent motion of multiple domains when the Dzyaloshinskii-Moriya interaction is taken into account.
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