Skyrmion spectroscopy in ferro- and antiferromagnets

结合理论和布里渊散射光谱学的专业知识，我们将探索铁磁和反铁磁薄膜中Skillrmion的磁本征模，包括它们在外部刺激下的激发。主要目的是为了了解和控制单天子和天米子晶格中的磁激发的一般情况。我们的主要实验工具将是布里渊散射光谱(BLS)。对于薄膜中的自旋激发，BLS优于其他现有的技术，因为它的高灵敏度允许检测各种对称性的热激发磁本征模，甚至从单个微结构。BLS已经发展成为量化薄膜中Dzyaloshinskii-Moriya相互作用强度的领先技术之一，我们将向SPP的所有成员提供这一实验工具，用于(比较)分析他们的层。这个项目的主要目的是利用最新的理论概念、模拟和BLS实验相结合的方法来解决天空米子激发的几个关键问题。第一个目标将是分析和理解室温下Skyrmion晶格和单个Skyrmion的热填充光谱。在这里，BLS提供了一种独特的方法来研究有限波矢的Skyrmion激发。第二个关键目标是在外部刺激存在的情况下对线性天米子激发的全面描述。作为刺激，我们将考虑射频磁场和自旋电流。从激发光谱中，我们将获得对支配天米子动力学的潜在过程的有价值的见解。作为第三个关键问题，我们将解决强外部驱动引起的非线性天米子激发及其对基于天米子的技术的影响，如天米子跑道存储器或用于射频应用的天米子纳米振荡器。在我们的室温实验中，我们将重点放在含有铁磁薄膜的层系统上，这些薄膜可以用于最先进的自旋电子器件，其中Skyrmion本征模通常具有GHz频率。为了将天子场扩展到更高的天米子速度和克服太赫兹带隙，上述每个目标还涵盖了对反铁磁体中相应现象的理论预测，在反铁磁体中，动力学本质上是不同的。这将包括反铁磁天米子激发的理论和在受控磁振子通量下的动力学。这些理论结合我们关于铁磁天米子动力学的实验结果，将勾勒出天米子光谱如何扩展到反铁磁动力学固有的太赫兹范围的途径，这为下一个周期设定了目标。这将激发关于反铁磁天微子的产生和操纵及其动力学的新颖实验。

Combining expertise in theory and in Brillouin light scattering spectroscopy, we will explore the magnetic eigenmodes of skyrmions in ferro- and antiferromagnetic thin films including their excitations due to external stimuli. The main objective is to obtain a general picture for understanding and controlling magnetic excitations within single skyrmions and within skyrmion lattices. Our main experimental tool will be Brillouin light scattering spectroscopy (BLS). Regarding spin excitations in thin films, BLS excels over other existing techniques, since its high sensitivity allows for the detection of thermally excited magnetic eigenmodes of various symmetries, even from individual microstructures. BLS has evolved into one of the leading techniques for the quantification of the strength of the Dzyaloshinskii-Moriya interaction in thin films, and we will offer this experimental tool to all members of the SPP for a (comparative) analysis of their layers. The main aim of this project is to address several key issues of skyrmion excitations using a combined approach of state-of-the-art theoretical concepts, simulations and BLS experiments. The first goal will be the analysis and understanding of the thermally populated spectra of skyrmion lattices and individual skyrmions at room temperature. Here, BLS provides a unique way to access skyrmion excitations with finite wave vector. The second key goal is a comprehensive picture of linear skyrmion excitations in the presence of external stimuli. As stimuli, we will consider radiofrequency magnetic fields and spin currents. From the excited spectra, we will obtain valuable insights into the underlying processes which govern the skyrmion dynamics. As the third key issue, we will address the nonlinear skyrmion excitations arising from strong external drivings and their implications for skyrmion-based technologies like skyrmion racetrack memories or skyrmion nano-oscillators for radiofrequency applications. In our room temperature experiments, we will focus on layer systems incorporating ferromagnetic thin films which can be used in state-of-the-art spintronic devices where skyrmion eigenmodes typically feature GHz frequencies. To extend the field of skyrmionics to higher skyrmion velocities and to overcome the THz gap, each of the aforementioned goals also covers theoretical predictions for the corresponding phenomena in antiferromagnets, where dynamics are substantially different. This will include theories for antiferromagnetic skyrmion excitations and dynamics under controlled magnon fluxes. These theories in combination with our experimental results on ferromagnetic skyrmion dynamics will outline the path how skyrmion spectroscopy can be extended to the THz range inherent to antiferromagnetic dynamics which sets the goal for the next cycle. This will stimulate novel experiments on the creation and manipulation of antiferromagnetic skyrmions and their dynamics.