Spin Waves bridging Spintronics and Photonics

这个项目的目标是探索自旋波、自旋极化电子和光子之间的基本联系，结合最近出现的磁振子学、自旋电子学和光子学这三个研究方向。这项研究是由对信息处理的新概念、新技术和新材料的需求推动的，因为一方面，由于余热的产生，电子设备正在达到其速度的物理极限，另一方面，光子学在小长度尺度上缺乏快速的电子控制。自旋波是频率从千兆赫到太赫兹的铁磁体的基本动态激励，它提供了独特的机会，将自旋电子学和光子学的最好方面结合在一起，为信息处理开辟了新的途径。在这个项目的范围内，有三个目标是感兴趣的：第一个目标是分析磁性纳米结构中的自旋波输运和操纵。这包括对新型材料和几何结构的表征，以及利用磁光克尔效应和布里渊光散射显微镜研究自旋波和磁畴壁之间的相互作用。第二个目标集中在自旋波和由自旋霍尔效应产生的自旋流之间的耦合。我们将通过自旋转移扭矩和自旋泵浦来分析自旋波的激发、放大和检测。在我们的第三个目标--纳米尺度的自旋波对光的操纵中，我们利用了自旋波和表面等离子体之间的强磁光耦合。这使得我们能够在自旋波定义的时间尺度上控制表面等离子体在纳米结构中的传播。探索一边是自旋波和电子，另一边是自旋波和光子之间的耦合机制，磁农学可以缩小自旋电子学和光子学之间的差距，这两种电子学仍然在不同的时间和长度尺度上运行。

The goal of this project is to explore fundamental connections between spin waves, spin polarized electrons and photons, combining the three recently emerged research directions of magnonics, spintronics and photonics. This research is driven by the demand for new concepts, technologies and materials for information processing since, on one side, electronics is reaching its physical limit of speed due to waste heat generation and, on the other side, photonics lacks fast, electronic control on small length scales. Spin waves, being the fundamental dynamic excitations of ferromagnets with frequencies in the gigahertz to terahertz regime, offer the unique opportunity to merge the best aspects of spintronics and photonics opening new pathways for information processing. Within the scope of this project, three objectives are in the focus of interest: The first objective is to analyze spin-wave transport and manipulation in magnetic nanostructures. This includes the characterization of novel materials and geometries as well as the investigation of the interactions between spin waves and domain walls utilizing the magneto-optical Kerr effect and Brillouin light scattering microscopy. The second objective focuses on the coupling between spin waves and spin currents that are created by the spin Hall-effect. We will analyze the excitation, amplification and detection of spin waves by spin transfer torque and spin pumping. Within our third objective, the manipulation of light by spin waves on the nanometer scale, we employ the strong magneto-optical coupling between spin waves and surface plasmons. This allows us to control the propagation of surface plasmons in nanostructures on the time scale defined by spin waves. Exploring mechanisms of coupling between spin waves and electrons on one side and spin waves and photons on the other, magnonics can close the gap between spintronics and photonics that still operate on different time and length scales.