Related Experiment Video
Updated: Jun 14, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Tunable magnons in a dual-gated 2D antiferromagnet
Nele Stetzuhn1,2, Abhijeet M Kumar3, Sviatoslav Kovalchuk3
1Department of Physics, Freie Universität Berlin, Berlin, Germany. nele.stetzuhn@fu-berlin.de.
Nature Communications
|June 12, 2026
Summary
We demonstrate electric-field control of magnons in 2D antiferromagnets. Applying an electric field tunes magnon frequencies in CrSBr devices, advancing gate-tunable magnonic technologies.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Layered antiferromagnets like CrSBr offer unique magnon properties due to coupling with other quasiparticles.
- Magnons in these materials are optically accessible, facilitating experimental investigation.
Purpose of the Study:
- Investigate the response of magnons in few-layered CrSBr devices to carrier density and electric fields.
- Understand the mechanism behind the asymmetric electric field response of magnons.
- Develop a model to describe magnetic dynamics in thin, non-uniformly doped devices.
Main Methods:
- Experimental investigation of few-layered CrSBr devices.
- Application of perpendicular electric fields and carrier density modulation.
- Development of a layer-resolved macrospin model for magnetic dynamics.
Main Results:
- Magnon frequencies increase with electron density.
- An asymmetric response of magnon modes to the applied electric field was observed.
- A layer-resolved macrospin model successfully described the observed magnetic dynamics.
- On-chip tunability of magnon frequencies by up to 2 GHz was achieved in a dual-gated trilayer device.
Conclusions:
- The study establishes dominant dependencies of magnetic properties on electron density and electric field in individual layers.
- Demonstrates the potential for gate-tunable magnonic devices based on 2D materials.
- Advances the application of 2D materials in spintronic and magnonic technologies.
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