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Updated: Aug 9, 2026
06:53
Scanning SQUID Study of Vortex Manipulation by Local Contact
Published on: February 1, 2017
Importance of the internal shape mode in magnetic vortex dynamics
Juan P Zagorodny1, Yuri Gaididei, Denis D Sheka
1Physics Institute, University of Bayreuth, 95440 Bayreuth, Germany. juan.zagorodny@uni-bayreuth.de
Physical Review Letters
|November 5, 2004
Summary
We studied vortex motion in magnets. Simulations show vortices follow circular paths at lower frequencies than the driving field, explained by a new theory accounting for vortex core dynamics.
Area of Science:
- Condensed matter physics
- Magnetism and magnetic materials
Background:
- Investigating magnetic vortex dynamics is crucial for understanding emergent phenomena in magnetic systems.
- The behavior of vortices under external magnetic fields is complex and requires advanced theoretical models.
Purpose of the Study:
- To analyze the motion of a nonplanar magnetic vortex in a circular easy-plane magnet.
- To develop a new theoretical framework for describing vortex dynamics coupled with internal degrees of freedom.
Main Methods:
- Numerical simulations of the Landau-Lifshitz equations for a many-spin system.
- Development of a collective variable theory incorporating internal vortex core dynamics.
Main Results:
- Observed vortex motion converging to a circular limit trajectory.
- Identified an orbit frequency lower than the driving magnetic field frequency.
- Derived collective variable evolution equations yielding limit-cycle solutions.
Conclusions:
- The new collective variable theory accurately describes the simulated vortex motion.
- Internal degrees of freedom of the vortex core significantly influence its translational dynamics.
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