平面螺旋磁体中电流和场驱动的畴壁动力学及手性切换
Current- and field-driven domain wall dynamics and chirality switching in a planar helimagnet
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中文总结 AI 辅助
研究电流和磁场对强易平面各向异性螺旋磁体手性动力学的影响，用连续统理论表明畴壁可由电流驱动，磁场中力矩绝热部分打破手性对称性，推导手性切换条件，数值模拟予以支持。
中文摘要 AI 辅助
我们研究了电流和磁场对具有强易平面各向异性的螺旋磁体中手性动力学的影响。利用为准一维近Lifshitz点的受挫铁磁体推导的连续统理论，表明连接相反手性畴的畴壁可由电流通过自旋转移力矩的耗散（非绝热）分量驱动。此外，证明了磁场存在时力矩的绝热部分打破了有效磁势能对手性的对称性。表明主导的对称破缺项出现在磁化梯度的三阶中，并推导了手性切换的条件。数值自旋晶格模拟支持了我们的结论。
英文摘要
We study the effect of electric current and magnetic field on the dynamics of chirality in a helimagnet with a strong easy-plane anisotropy. Using a continuum theory, derived for a quasi-one-dimensional frustrated ferromagnet close to the Lifshitz point, we show that a domain wall connecting domains with opposite chiralities can be driven by the current via the dissipative (non-adiabatic) component of the spin-transfer torque. Further, it is demonstrated that the adiabatic part of the torque in the presence of a magnetic field breaks the symmetry of the effective magnetic potential energy with respect to the chirality. We show that the leading symmetry-breaking term arises in the third order in the magnetization gradient, and derive the conditions of the chirality switching. Our conclusions are supported by numerical spin-lattice simulations.
