具有垂直各向异性的交换耦合弹簧系统的磁化动力学
Magnetisation dynamics in exchange coupled spring systems with perpendicular anisotropy
摘要：
在交换弹簧磁铁的磁化动力学进行了研究，使用模拟的FePt/Fe双层系统。FePt硬层表现出强的垂直磁晶各向异性，而软（Fe）层具有可忽略的磁晶各向异性。Fe层中的局部自旋取向的变化由与硬层的交换耦合相互作用和有利于面内磁化的静磁能的竞争决定。动态进行了研究，通过监测Fe层磁化强度的响应后，突然应用的磁场，导致系统重新排列通过进动运动。这种进动运动使我们能够获得频谱，从而检查动态磁化运动。由于软层中自旋的旋转不具有良好定义的磁各向异性，因此该系统不呈现薄膜的通常频率场特性。此外，我们获得多峰的共振谱的应用程序的磁场垂直的膜平面，虽然我们折扣的自旋波模式的存在，并提出这是由于在整个Fe层的局部有效场的变化。动态响应仅在Fe层中考虑，FePt层保持固定在垂直取向。
英文摘要：
Magnetisation dynamics in exchange spring magnets have been studied using simulations of the FePt/Fe bilayer system. The FePt hard layer exhibits strong perpendicular magnetocrystalline anisotropy, while the soft (Fe) layer has negligible magnetocrystalline anisotropy. The variation of the local spin orientation in the Fe layer is determined by the competition of the exchange coupling interaction with the hard layer and the magnetostatic energy which favours in-plane magnetisation. Dynamics were studied by monitoring the response of the Fe layer magnetisation after the abrupt application of a magnetic field which causes the systems to realign via precessional motion. This precessional motion allows us to obtain the frequency spectrum and hence examine the dynamical magnetisation motion. Since the rotation of the spins in the soft layer does not have a well defined magnetic anisotropy, the system does not present the usual frequency field characteristics for a thin film. Additionally we obtain multi-peaked resonance spectra for the application of magnetic fields perpendicular to the film plane, though we discount the existence of spin wave modes and propose that this arises due to variations in the local effective field across the Fe layer. The dynamic response is only considered in the Fe layer, with the FePt layer held fixed in the perpendicular orientation.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
