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Published on: October 5, 2013
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Moiré magnetism in CrBr3 multilayers emerging from differential strain.
Fengrui Yao1,2, Dario Rossi3, Ivo A Gabrovski4
1Department of Quantum Matter Physics, University of Geneva, Geneva, Switzerland. fengrui.yao@unige.ch.
Nature Communications
|November 29, 2024
Summary
Researchers demonstrate differential strain in van der Waals (vdW) materials can create moiré-like superlattices. This strain induces spatially modulated spin textures, leading to simultaneous ferromagnetic and antiferromagnetic regions in CrBr3, mimicking moiré magnetism.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Moiré superlattices in twisted 2D materials exhibit unique physical phenomena.
- Creating long periodicities via differential strain in van der Waals (vdW) materials is theoretically proposed but experimentally unexplored.
Purpose of the Study:
- To experimentally investigate the creation of moiré-like superlattices using differential strain in vdW materials.
- To explore the resulting magnetic properties and spin textures.
Main Methods:
- Fabrication of CrBr3 tunnel barriers with ferromagnetic Fe3GeTe2 and graphene electrodes.
- Measurement of magnetoconductance in response to temperature and magnetic field.
- Raman spectroscopy and theoretical modeling.
Main Results:
- Observed unexpected magnetoconductance in CrBr3 tunnel barriers, indicative of simultaneous ferromagnetic and antiferromagnetic regions.
- Magnetoconductance behavior mimics that of small-angle twisted CrBr3 junctions exhibiting moiré magnetism.
- Differential strain in CrBr3 was identified as the cause, modifying stacking and interlayer exchange.
Conclusions:
- Differential strain is a viable experimental strategy for creating moiré-like superlattices in vdW multilayers.
- This approach leads to spatially modulated spin textures and moiré magnetism.
- Offers potential for in-situ, continuous tunability of magnetic properties at low temperatures.
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