论文标题
通过使用内部动力学来降低双轴纳米颗粒中磁化转换的能源成本
Reduction of energy cost of magnetization switching in a biaxial nanoparticle by use of internal dynamics
论文作者
论文摘要
提出了一种用双轴各向异性的纳米颗粒中的节能磁化切换的解决方案。最小化磁化反转的能量成本的最佳控制路径是数值计算的，作为切换时间和材料属性的功能，用于得出外部磁场的节能开关脉冲。硬轴各向异性降低了由于内部扭矩在所需的开关方向上引起的磁化切换的最低能量成本。根据扰动理论获得了量化此效果的分析估计。获得了快速切换和能源效率之间的权衡的最佳切换时间。可以在双轴纳米磁铁中独立控制开关的能源成本和稳定状态之间的能屏障。这为节能的写入与磁性记忆元件的良好热稳定性之间的困境提供了解决方案。
A solution to energy-efficient magnetization switching in a nanoparticle with biaxial anisotropy is presented. Optimal control paths minimizing the energy cost of magnetization reversal are calculated numerically as functions of the switching time and materials properties, and used to derive energy-efficient switching pulses of external magnetic field. Hard-axis anisotropy reduces the minimum energy cost of magnetization switching due to the internal torque in the desired switching direction. Analytical estimates quantifying this effect are obtained based on the perturbation theory. The optimal switching time providing a tradeoff between fast switching and energy efficiency is obtained. The energy cost of switching and the energy barrier between the stable states can be controlled independently in a biaxial nanomagnet. This provides a solution to the dilemma between energy-efficient writability and good thermal stability of magnetic memory elements.
