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Giant self spin-valve effect in the kagome helimagnet
Xitong Xu1,2, Yonglai Liu3,4, Kesen Zhao3,4
1Anhui Key Laboratory of Low-Energy Quantum Materials and Devices, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, Anhui, 230031, China. xuxitong@hmfl.ac.cn.
Nature Communications
|March 18, 2025
Summary
Researchers discovered a self spin-valve effect in kagome magnets, specifically TmMn6Sn6. This intrinsic effect leads to a giant magnetoresistance (GMR) ratio over 160%, paving the way for novel spintronics applications.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- Kagome magnets offer a unique platform for exploring quantum phenomena due to their combination of non-trivial band topology and electron correlations.
- Frustrated interlayer interactions in kagome magnets are investigated for their potential to host novel quantum effects.
Purpose of the Study:
- To propose and experimentally verify the existence of an intrinsic self spin-valve effect in kagome magnets.
- To investigate the behavior of TmMn6Sn6 under an applied magnetic field and its potential for spintronic applications.
Main Methods:
- Theoretical proposal of the self spin-valve effect in frustrated kagome magnets.
- Experimental confirmation using the kagome helimagnet TmMn6Sn6.
- Magnetic force microscopy to observe domain structures under perpendicular magnetic fields.
Main Results:
- Observation of stripe domains stacking along the helical axis in TmMn6Sn6 under a magnetic field.
- Attribution of these domains to the loss of stability in the kagome helimagnetic state.
- Achieved a giant magnetoresistance (GMR) ratio exceeding 160% due to the intrinsic spin-valve effect and high spin polarization.
Conclusions:
- Kagome magnets with frustrated interlayer interactions can intrinsically exhibit a self spin-valve effect.
- TmMn6Sn6 serves as an experimental demonstration of this phenomenon, mimicking artificial spin valves.
- This finding opens new possibilities for developing inherent spin valves in quantum magnets for future spintronics.
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