Transmission electron microscopy is one of the most powerful techniques to characterize nanoscale magnetic structures. In light of the importance of fast control schemes of magnetic states, time-resolved microscopy techniques are highly sought after in fundamental and applied research. Here, we implement time-resolved Lorentz imaging in combination with synchronous radio-frequency excitation using an ultrafast transmission electron microscope. As a model system, we examine the current-driven gyration of a vortex core in a 2 μm-sized magnetic nanoisland. We record the trajectory of the vortex core for continuous-wave excitation, achieving a localization precision of ±2 nm with few-minute integration times. Furthermore, by tracking the core position after rapidly switching off the current, we find a transient increase of the free oscillation frequency and the orbital decay rate, both attributed to local disorder in the vortex potential.

透射电子显微镜是表征纳米级磁性结构的最强大技术之一。鉴于磁态快速控制方案的重要性，在基础研究和应用研究中都强烈要求采用时间分辨显微镜技术。在这里，我们结合使用超快速透射电子显微镜的同步射频激励来实现时间分辨的Lorentz成像。作为模型系统，我们检查了2μm大小的磁性纳米岛中涡流核的电流驱动回转。我们记录了连续波激发的涡旋芯的轨迹，在几分钟的积分时间内实现了±2 nm的定位精度。此外，通过在迅速切断电流后跟踪核心位置，