Helmholtz-Zentrum Dresden-Rossendorf, 01328 Dresden, Germany.
Technische Universität Dresden, 01069 Dresden, Germany.
Nat Nanotechnol. 2016 Nov;11(11):948-953. doi: 10.1038/nnano.2016.117. Epub 2016 Jul 18.
The use of spin waves as information carriers in spintronic devices can substantially reduce energy losses by eliminating the ohmic heating associated with electron transport. Yet, the excitation of short-wavelength spin waves in nanoscale magnetic systems remains a significant challenge. Here, we propose a method for their coherent generation in a heterostructure composed of antiferromagnetically coupled magnetic layers. The driven dynamics of naturally formed nanosized stacked pairs of magnetic vortex cores is used to achieve this aim. The resulting spin-wave propagation is directly imaged by time-resolved scanning transmission X-ray microscopy. We show that the dipole-exchange spin waves excited in this system have a linear, non-reciprocal dispersion and that their wavelength can be tuned by changing the driving frequency.
自旋波可用作自旋电子器件中的信息载体，通过消除与电子输运相关的欧姆加热，可以显著降低能量损耗。然而，在纳米尺度磁性系统中激发短波长自旋波仍然是一个重大挑战。在这里，我们提出了一种在由反铁磁耦合磁性层组成的异质结构中相干产生它们的方法。利用自然形成的纳米级堆叠磁涡旋核对的驱动动力学来实现这一目标。通过时间分辨扫描透射 X 射线显微镜直接对产生的自旋波传播进行成像。我们表明，在该系统中激发的偶极交换自旋波具有线性、非互易色散，并且通过改变驱动频率可以调节它们的波长。
