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arXiv · 1801.06748

Microwave fields driven domain wall motions in antiferromagnetic nanowires

Abstract

In this work, we study the microwave field driven antiferromagnetic domain wall motion in an antiferromagnetic nanowire, using the numerical calculations based on a classical Heisenberg spin model. We show that a proper combination of a static magnetic field plus an oscillating field perpendicular to the nanowire axis is sufficient to drive the domain wall propagation along the nanowire with the axial magnetic anisotropy. More importantly, the drift velocity at the resonance frequency is comparable to that induced by temperature gradients, suggesting that microwave field can be a very promising tool to control domain wall motions in antiferromagnetic nanostructures. Furthermore, the dependences of resonance frequency and drift velocity on the static and oscillating fields, the axial anisotropy, and the damping constant are discussed in details. This work provides useful information for the spin dynamics in antiferromagnetic nanostructures for spintronics applications.

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Z. Y. Chen, Z. R. Yan, Y. L. Zhang, M. H. Qin, Z. Fan, X. B. Lu, X. S. Gao, J. M. Liu. 2018-01-21. Microwave fields driven domain wall motions in antiferromagnetic nanowires. https://doi.org/10.1088/1367-2630%2Faac68e

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