Strain-mediated magnetoelectric effect for the electric-field control of magnetic states in nanomagnets
Strain-mediated magnetoelectric effect for the electric-field control of magnetic states in nanomagnets
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DOI：
10.1007/s00707-017-2029-7
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发表时间：
2017-11
期刊：
影响因子：
2.7
通讯作者：
M. Yi;Bai-Xiang Xu;R. Müller;D. Gross
中科院分区：
文献类型：
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作者：
M. Yi;Bai-Xiang Xu;R. Müller;D. Gross
没有电流的磁场的电场控制潜在地使自旋电子学朝着超低功率方向发生革命性变化。在这里，我们通过机械耦合相场模拟，计算演示了应变介导的磁电效应在异质结构中磁态电场控制中的应用。在由软纳米磁体Co和压电性衬底PMN-PT组成的模型中，研究了电场激发下的磁态波动性和磁化强度转换动力学。研究发现，电场可以驱动单畴纳米磁体进入平衡涡旋态。即使在去掉电场或施加反向电场后，纳米磁体仍然处于涡旋态，即涡旋态是非常稳定和不挥发的。只有利用进动磁化动力学，才有可能在没有稳定涡旋态的小尺寸纳米磁体中实现180磁化转换。如果电场大小、脉冲宽度和斜坡时间设计得当，电场脉冲可以实现确定性的180开关。最小开关时间小于10 ns。这些结果为低功耗、可靠、快速的电场控制自旋电子学的设计提供了有用的信息。
Electric-field control of magnetism without electric currents potentially revolutionizes spintronics toward ultralow power. Here, by using mechanically coupled phase field simulations, we computationally demonstrate the application of the strain-mediated magnetoelectric effect for the electric-field control of magnetic states in a heterostructure. In the model heterostructure constituted of the soft nanomagnet Co and the piezoelectric substrate PMN–PT, both the volatility of magnetic states and the magnetization switching dynamics excited by the electric field are explored. It is found that an electric field can drive the single-domain nanomagnet into an equilibrium vortex state. The nanomagnet remains in the vortex state even after removing the electric field or applying a reverse electric field, i.e., the vortex state is extremely stable and nonvolatile. Only by utilizing the precessional magnetization dynamics, the 180magnetization switching is possible in small-sized nanomagnets which are free of the stable vortex state. Electric-field pulses can realize the deterministic 180switching if the electric-field magnitude, pulse width, and ramp time are carefully designed. The minimum switching time is found to be less than 10 ns. These results provide useful information for the design of low-power, reliable, and fast electric-field-controlled spintronics.