Few-nm tracking of current-driven magnetic vortex orbits using ultrafast Lorentz microscopy
| Autor: | Marcel Möller, Claus Ropers, Sascha Schäfer, John H. Gaida |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
Permalloy
Physics Rotation around a fixed axis General Physics and Astronomy lcsh:Astrophysics 02 engineering and technology 021001 nanoscience & nanotechnology Tracking (particle physics) 01 natural sciences Gyration lcsh:QC1-999 Computational physics Vortex Condensed Matter::Materials Science Temporal resolution 0103 physical sciences Microscopy lcsh:QB460-466 010306 general physics 0210 nano-technology Excitation lcsh:Physics |
| Zdroj: | Communications Physics Communications Physics, Vol 3, Iss 1, Pp 1-7 (2020) |
| Popis: | 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. Imaging the dynamic behaviour of magnetic textures with high spatial and temporal resolution is challenging. Here, the authors use ultrafast Lorentz microscopy to study the rotational motion of a magnetic vortex core in a permalloy nanoisland, excited by sinusoidal radio-frequency currents. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|