论文标题
探测以亚NM分辨率的磁涡流核的固定强度
Probing the Pinning Strength of Magnetic Vortex Cores with sub-nm Resolution
论文作者
论文摘要
拓扑磁纹理（例如涡流核心或天际）是非易失性信息处理的关键候选者。这通过固定通常会反对的电流脉冲来利用质地运动。因此，对固定的详细理解是至关重要的，先前的实验在受控磁纹理定位或空间分辨率方面受到限制。在这里，我们使用自旋极化扫描隧道显微镜来跟踪3D磁场故意移动的磁性涡流芯。覆盖约10.000 fe原子的核心被相距仅几个nm的缺陷所固定。通过参数拟合重现涡旋路径，我们推断出缺陷的固定潜力，因为墨西哥帽子具有短距离排斥和远程有吸引力的部分。通过与微磁模拟相比，有吸引力的部分归因于局部抑制交换相互作用。在子-NM量表上推断出缺陷诱导的固定电势的新型方法可将其转移到其他非类别旋转纹理上，最终可以实现缺陷配置的原子量表设计，例如，在Race-Track Type类型设备中可靠读出。
Topological magnetic textures such as vortex cores or skyrmions are key candidates for non-volatile information processing. This exploits the texture movement by current pulses that is typically opposed by pinning. A detailed understanding of pinning is hence crucial with previous experiments being either limited in terms of controlled magnetic texture positioning or in terms of spatial resolution. Here, we use spin-polarized scanning tunneling microscopy to track a magnetic vortex core that is deliberately moved by a 3D magnetic field. The core covering about 10.000 Fe-atoms gets pinned by defects that are only a few nm apart. Reproducing the vortex path via parameter fit, we deduce the pinning potential of the defects as a mexican hat with short-range repulsive and long-range attractive part. By comparison with micromagnetic simulations, the attractive part is attributed to a local suppression of exchange interaction. The novel approach to deduce defect induced pinning potentials on the sub-nm scale is transferable to other non-collinear spin textures eventually enabling an atomic scale design of defect configurations, e.g., for reliable read-out in race-track type devices.
