Realizing Quantitative Quasiparticle Modeling of Skyrmion Dynamics in Arbitrary Potentials
Maarten A Brems1, Tobias Sparmann1, Simon M Fröhlich1
1Johannes Gutenberg University Mainz, Institute of Physics, 55099 Mainz, Germany.
Physical Review Letters
|February 14, 2025
Summary
We calibrated Thiele model simulations for magnetic skyrmion dynamics, enabling quantitative analysis of pinning landscapes and diffusion. This allows precise inference of forces acting on skyrmions using ultralow current densities.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Computational Physics
Background:
- Magnetic skyrmions are topologically protected spin textures with potential applications in data storage and neuromorphic computing.
- Simulating magnetic skyrmion dynamics accurately on large length and time scales is crucial for experimental validation and device design.
- Existing models often lack key parameters to bridge the gap between simulation and experimental observations.
Purpose of the Study:
- To develop a fully quantitative Thiele model for magnetic skyrmion dynamics.
- To enable simulations on experimentally relevant large length and time scales.
- To determine spatial pinning energy landscapes for skyrmion diffusion studies.
Main Methods:
- Ascertaining missing parameters to calibrate experimental and simulation timescales.
- Calibrating current-induced forces acting on magnetic skyrmions.
- Utilizing the Lifson-Jackson framework for diffusion quantification in arbitrary potentials.
Main Results:
- Demonstrated fully quantitative Thiele model simulations of magnetic skyrmion dynamics.
- Achieved simulations on previously unattainable large length and time scales.
- Determined complete spatial pinning energy landscapes.
- Inferred total force on skyrmions by isolating ultralow current density (10^6 A/m^2) generated torques.
Conclusions:
- The developed method allows for precise quantification of experimental studies on skyrmion diffusion.
- Enables accurate modeling of skyrmion behavior under ultralow current densities.
- Provides a pathway for direct inference of forces acting on skyrmions, advancing quantitative magnetic skyrmion research.
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