Current-induced motion of antiskyrmions in Heusler thin films

磁性skyrmions和anti-skyrmions是拓扑保护的手性磁性纳米物体，是未来高密度、高能效的赛道存储器件的潜在信息载体。在第一轮的SPP中，我们利用Lorentz透射电子显微镜（LTEM）和磁力显微镜（MFM）研究了反回旋共振系统中反回旋共振的厚度无关的内禀稳定性，反回旋共振系统中反回旋共振的尺寸的鲁棒可调性以及由于长程偶极-偶极相互作用而引起的椭圆Bloch回旋共振的稳定性。到目前为止，我们还没有发现任何证据的反kyrmions的运动使用体积自旋转移扭矩在层状形成的大块晶体。我们目前的建议集中在超薄外延Heusler薄膜的生长，可以hostantiskyrmions和从中我们可以制备磁性racetrackswith的主要目标是演示电流诱导的操纵反kyrmions使用相邻的金属层的自旋轨道扭矩。为了实现这一目标，我们将探索超薄Heusler薄膜的生长使用新的化学模板层（CTL）。后者已被用来形成二元四方化合物，这是化学有序，即使在室温下沉积。CTL方法使用具有原子有序的CsCl结构的化合物，如CoAl、IrAl和该家族的其他成员（作为底层）。我们最初的重点将是在较厚的D2 d Heusler薄膜中稳定单个反回旋共振。我们的下一个重点将是证明在超薄膜中反回旋子的形成，只有一个或两个单位细胞厚，并探索反回旋子在自旋轨道扭矩下的运动。一个重要的目标是生长基于Heusler的合成反铁磁（SAF）结构，其中两个垂直磁化的铁磁Heusler子层通过金属RuAl间隔层介导的反铁磁层间交换相互作用耦合，与铁磁材料中的反kyrmion不同，SAF中的耦合反kyrmion完全不受kyrmion Hall效应的影响。为了生长这些薄膜磁控共溅射，以及低压，离子束溅射能力与threesands和多个目标将采用最近beendesigned和建立在MPI-哈雷。将采用变温LTEM、MFM、STXM和Kerr显微镜等多种磁成像技术的组合来研究电流诱导运动。

Magnetic skyrmions and antiskyrmions are topologically protectedchiral magnetic nano-objects, which are potential information carriersfor future dense and energy-efficient racetrack memory devices. Inthe first round of this SPP, by employing Lorentz transmission electronmicroscopy (LTEM) and magnetic force microscopy (MFM), weshowed the thickness-independent intrinsic stability of antiskyrmions,robust tunability of the size of antiskyrmions and stabilization ofelliptical Bloch skyrmions in the antiskyrmions system due to longrangedipole-dipole interactions. To date, we have found no evidencefor the motion of antiskyrmions using volume spin transfer torques inlamellae formed from bulk crystals. Our current proposal focuses onthe growth of ultra-thin epitaxial Heusler films that could hostantiskyrmions and from which we can prepare magnetic racetrackswith the principle objective of demonstrating the current-inducedmanipulation of antiskyrmions using spin-orbit torques from adjacentheavy metal layers. To achieve this objective we will explore thegrowth of ultra-thin Heusler films using novel chemical templatinglayers (CTL). The latter have been used to form binary tetragonalcompounds, which are chemically ordered even for room temperaturedeposition. The CTL method uses compounds such as CoAl, IrAl andother members of this family (as an underlayer) with the CsClstructure that are atomically ordered. Our initial focus will be tostabilize individual antiskyrmions in thicker D2d Heusler films. Ournext focus will be to demonstrate the formation of antiskyrmions inultra-thin films, just one or two unit cells thick and exploring the motionof antiskyrmions under spin orbit torques. An important objective willbe to grow Heusler-based synthetic antiferromagnetic (SAF)structures, where two perpendicularly magnetized ferromagneticHeusler sub-layers are coupled via antiferromagnetic interlayerexchange interaction mediated by ultrathin metallic RuAl spacer layer.Unlike antiskyrmions in ferromagnetic materials, coupledantiskyrmions in SAFs are completely free from the influence of theskyrmion Hall effect. To grow these films magnetron co-sputtering, aswell as a low pressure, ion beam sputtering capability with threesources and multiple targets will be employed that has recently beendesigned and built at the MPI-Halle. A combination of variousmagnetic imaging techniques including variable temperatures LTEM,MFM, STXM and Kerr microscopy will be used to study the currentinducedmotion.