Hertel R, Gliga S, Fähnle M, Schneider C M
Institut für Festkörperforschung IFF-9 Elektronische Eigenschaften, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany.
Phys Rev Lett. 2007 Mar 16;98(11):117201. doi: 10.1103/PhysRevLett.98.117201. Epub 2007 Mar 12.
We present an ultrafast route for a controlled, toggle switching of magnetic vortex cores with ultrashort unipolar magnetic field pulses. The switching process is found to be largely insensitive to extrinsic parameters, like sample size and shape, and it is faster than any field-driven magnetization reversal process previously known from micromagnetic theory. Micromagnetic simulations demonstrate that the vortex core reversal is mediated by a rapid sequence of vortex-antivortex pair creation and annihilation subprocesses. Specific combinations of field-pulse strength and duration are required to obtain a controlled vortex core reversal. The operational range of this reversal mechanism is summarized in a switching diagram for a 200 nm Permalloy disk.
我们展示了一种利用超短单极磁场脉冲对磁涡旋核进行可控、翻转切换的超快途径。发现该切换过程在很大程度上对外在参数（如样品尺寸和形状）不敏感，并且比之前从微磁学理论得知的任何场驱动磁化反转过程都要快。微磁学模拟表明，涡旋核反转是由涡旋 - 反涡旋对的快速产生和湮灭子过程序列介导的。需要特定的场脉冲强度和持续时间组合来实现可控的涡旋核反转。这种反转机制的操作范围总结在一个200纳米坡莫合金盘的切换图中。
