Magnetic properties of van der Waals ferromagnet Fe₃GeTe₂ nanosheets grown by flux-assisted growth

Among two-dimensional (2D) van der Waals (vdW) materials, Fe₃GeTe₂ (FGT), a 2D vdW ferromagnetic material, has gained significant interest due to its high Curie temperature and perpendicular magnetic anisotropy. Despite the difficulties in fabricating high-quality crystals, the flux-assisted growth (FAG) method has recently emerged as a promising technique for synthesizing 2D vdW materials. In this study, we employed the FAG method to fabricate crystalline FGT nanosheets under varied growth parameters. Magneto-optical Kerr effect (MOKE) measurements revealed that the FGT nanosheets exhibit perpendicular magnetic anisotropy with a Curie temperature of 222 K. Additionally, the MOKE data indicate the presence of exchange bias phenomena, likely due to the FeO phase associated with oxidized FGT surface. These findings enhance our understanding of the fundamental physics of FGT nanosheets and contribute to the advancement of diverse 2D magnetic device applications.