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Direct Observation of Sublattice-Dependent Magnetic Ordering and Strong Electron-Magnon Coupling in Fe_{5}GeTe_{2}
R Xu1,2, X H Chen1,2, X L Li1,2
1University of Science and Technology of China, Hefei National Research Center for Physical Sciences at Microscale and School of Emerging Technology, Hefei 230026, China.
Physical Review Letters
|July 10, 2026
Summary
Researchers investigated the room-temperature ferromagnet Fe_{5}GeTe_{2}, uncovering how sublattice spin order influences its electronic and magnetic properties. This reveals a new method for tuning two-dimensional magnets.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Magnetism
Background:
- Van der Waals magnets like Fe_{5}GeTe_{2} show promise for applications but their fundamental properties lack microscopic understanding.
- Investigating the interplay between electronic structure and magnetism is crucial for advancing two-dimensional (2D) magnetic materials.
Purpose of the Study:
- To elucidate the microscopic origins of the magnetic and transport properties in Fe_{5}GeTe_{2}.
- To understand the relationship between electronic structure, electron-magnon coupling, and sublattice magnetism.
Main Methods:
- Angle-resolved photoemission spectroscopy (ARPES) to probe electronic structure.
- Density functional theory (DFT) calculations to model magnetic configurations and electronic properties.
- Analysis of resistivity and magnetic susceptibility measurements.
Main Results:
- The electronic structure consistent with an up-up-up spin configuration was resolved.
- A significant Fermi surface reconstruction and a 25 meV dispersion kink indicating strong electron-magnon coupling were observed near 105 K.
- Emergence of Fe(1) sublattice spin order was identified as the key driver for observed phenomena.
Conclusions:
- Sublattice-dependent magnetism critically governs the coupled electronic and magnetic behavior in Fe_{5}GeTe_{2}.
- Sublattice engineering offers a viable strategy for tailoring correlated phenomena in 2D magnets.
- This study provides fundamental insights into the mechanisms behind exotic properties in van der Waals ferromagnets.
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