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Dynamics of Current-Induced Switching in the Quantum Anomalous Hall Effect
Alina Rupp1, Daniel Rosenbach1, Torsten Röper1
1Universität zu Köln, II. Physikalisches Institut, Zülpicher Strasse 77, D-50937 Köln, Germany.
Physical Review Letters
|March 13, 2026
Summary
Researchers studied ferromagnetic topological insulators and found that electrical bias can flip edge state direction. This magnetization reversal is thermally activated by Joule heating, enabling control over chiral edge states.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Ferromagnetic topological insulators exhibit chiral edge states in the quantum anomalous Hall (QAH) regime.
- These dissipationless states have propagation directions dictated by the material's magnetization.
Purpose of the Study:
- Investigate the dynamics of magnetization switching in QAH systems.
- Explore the potential for controlling chiral edge states via electrical bias.
Main Methods:
- Utilized time-resolved measurements to observe magnetization reversal.
- Analyzed the switching dynamics under electrical current pulses.
Main Results:
- Observed characteristics indicative of a disordered magnetic landscape.
- Demonstrated that magnetization reversal is a thermally activated process.
- Identified Joule heating during current pulses as the driving mechanism.
Conclusions:
- Magnetization dynamics in QAH systems are influenced by thermal effects.
- Joule heating provides a pathway for manipulating chiral edge states.
- Opens avenues for local, controlled manipulation of edge states in QAH materials.
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