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The developing material class of van der Waals (vdW) magnets has attracted great interest due to their novel properties such as gate and strain tunable magnetism. Magnetism at the atomic limit remains difficult to explore however due to the air instability of most vdW ferromagnets. In this work, we demonstrate that pre-fabricated Hall bar electrodes can be used to probe magnetism in Fe3GeTe2 (FGT) flakes via the anomalous Hall effect. Utilizing this device structure, we systematically investigated the magnetic properties of FGT. Clear ferromagnetic hysteresis windows were clearly observed at temperatures up to 200 K. These vdW Hall bar structures provides a highly efficient and damage-free strategy for metal integration, which could be used in many other 2D magnetic materials.
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Quantum Stoner–Wohlfarth model of two-dimensional single-domain magnets
The Stoner–Wohlfarth model is a classical model for magnetic hysteresis of single-domain magnets. For two-dimensional (2D) magnets at finite temperatures, the Stoner–Wohlfarth model must be extended to include intrinsic strong spin fluctuations. We predict several fundamentally different hysteresis properties between 2D and 3D magnets. The magnetization switching diagram known as the astroid figure in the conventional Stoner–Wohlfarth model becomes highly temperature dependent and asymmetric with respect to the transverse and longitudinal magnetic fields. Our results provide new insights into the spintronics applications based on 2D magnetic materials.
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- Award ID(s):
- 2011331
- PAR ID:
- 10410815
- Date Published:
- Journal Name:
- Journal of Applied Physics
- Volume:
- 133
- Issue:
- 16
- ISSN:
- 0021-8979
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1063/5.0143593
