论文标题
Bifeo $ _3 $/COFE异质结的切换动力学的微磁性研究
A micromagnetic study of the switching dynamics of the BiFeO$_3$/CoFe heterojunction
论文作者
论文摘要
建模单域BifeO3/COFE异质结的开关动力学，并从实验结果中提取关键参数，例如接口交换耦合系数。从理论上量化了BifeO3/COFE异质结中COFE磁性响应时间的下限，以达到100 ps的阶。我们的结果表明，BifeO3/COFE异质结中COFE的开关行为由BifeO3中的Neel Vector的旋转而不是界面上的单向交换偏置旋转。我们还通过将我们的仿真结果与巨磁磁性（GMR）曲线和实验中的磁性磁滞回路进行比较，将接口交换耦合系数J_INT的大小量化为0.32 PJ/m。据我们所知，这是第一次从实验中定量提取J_INT。此外，我们证明，可以通过降低COFE的厚度并增加BifeO3/COFE异质结的长度与宽度纵横比，可以改善BifeO3/COFE异质结的开关成功率和热稳定性。我们的理论模型提供了一个全面的框架，以研究BifeO3/COFE异质结中COFE的磁性特性和操纵COFE的磁性。
The switching dynamics of a single-domain BiFeO3/CoFe heterojunction is modeled and key parameters such as interface exchange coupling coefficient are extracted from experimental results. The lower limit of the magnetic order response time of CoFe in the BiFeO3/CoFe heterojunction is theoretically quantified to be on to the order of 100 ps. Our results indicate that the switching behavior of CoFe in the BiFeO3/CoFe heterojunction is dominated by the rotation of the Neel vector in BiFeO3 rather than the unidirectional exchange bias at the interface. We also quantify the magnitude of the interface exchange coupling coefficient J_int to be 0.32 pJ/m by comparing our simulation results with the giant magnetoresistance (GMR) curves and the magnetic hysteresis loop in the experiments. To the best of our knowledge, this is the first time that J_int is extracted quantitatively from experiments. Furthermore, we demonstrate that the switching success rate and the thermal stability of the BiFeO3/CoFe heterojunction can be improved by reducing the thickness of CoFe and increasing the length to width aspect ratio of the BiFeO3/CoFe heterojunction. Our theoretical model provides a comprehensive framework to study the magnetoelectric properties and the manipulation of the magnetic order of CoFe in the BiFeO3/CoFe heterojunction.
