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Slow Equilibrium Relaxation in a Chiral Magnet Mediated by Topological Defects.
Chenhao Zhang1, Yang Wu1, Jingyi Chen1
1ShanghaiTech University, School of Physical Science and Technology, Shanghai 201210, China.
Physical Review Letters
|November 1, 2024
Summary
Chiral magnets like Cu2OSeO3 exhibit slow magnetic order relaxation, taking 0.2 seconds due to topological defects. This reveals universal dynamics in solitonic textures for information storage.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Topological Physics
Background:
- Chiral magnets host complex noncollinear magnetic orders.
- Understanding magnetic relaxation dynamics is crucial for magnetic storage technologies.
Purpose of the Study:
- To investigate the relaxation dynamics of noncollinear magnetic orders in the chiral magnet Cu2OSeO3.
- To determine the timescale of magnetic stabilization after perturbation.
Main Methods:
- Pump-probe experiment utilizing a millisecond magnetic field pulse (pump).
- Resonant elastic x-ray scattering (REXS) as the probe technique.
- Studied both conical and skyrmion lattice magnetic phases.
Main Results:
- The chiral magnet Cu2OSeO3 exhibited a slow relaxation time of approximately 0.2 seconds.
- This relaxation timescale is significantly longer than the nanosecond dynamics typical in micromagnetics.
- Prolonged relaxation is linked to the formation and slow dissipation of topological defects, such as emergent monopoles.
Conclusions:
- Topological defects, like emergent monopoles, play a key role in the slow relaxation dynamics of chiral magnets.
- The study highlights a universal relaxation mechanism in solitonic textures within a slow dynamics regime.
- Findings offer insights into topological physics and potential applications in advanced information storage.
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