van der Waals (vdW) magnetic materials show promise in being the foundation for future spintronic technology. The magnetic behavior of Fe2.7GeTe2 (FGT), a vdW itinerant ferromagnet, was investigated before and after proton irradiation. Proton irradiation of the sample was carried out at a fluence of 1×1018 cm-2. The magnetization measurements revealed a small increase of saturation magnetization (Ms) of about 4% upon proton irradiation of the sample, in which, the magnetic field was applied parallel to the c-axis. X-ray photoelectron spectroscopy for pristine and irradiated FGT revealed a general decrease in intensity after irradiation for Ge and Te and an increase in peak intensity of unavoidable surface iron oxide. Furthermore, no noticeable change in the Curie temperature (TC =152 K) is observed in temperature dependent magnetization variation. This work signifies the importance of employing protons in tuning the magnetic properties of vdW materials.
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Probing Ferromagnetism in van der Waals Iron Germanium Telluride
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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- Award ID(s):
- 1653241
- PAR ID:
- 10328634
- Date Published:
- Journal Name:
- 52th IEEE Semiconductor Interface Specialists Conference
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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