Local pressure-induced modulation of perpendicular magnetic property in van der Waals ferromagnetic Fe3GaTe2 flakes using atomic force microscopy

In two-dimensional van der Waals (vdW) materials, interlayer coupling governed by the vdW gap strongly influences their physical properties. In this study, we apply localized GPa-scale pressure to Fe 3 GaTe 2 (FGaT) flakes via atomic force microscope (AFM) tip rubbing and investigate the resulting magnetic response using Kerr microscopy and Raman spectroscopy. Under an estimated pressure of ∼7 GPa applied over a 5 × 5 μm² area, the nucleation field (Hₙ) of FGaT flakes with thicknesses of 50–400 nm is significantly reduced. The changes in Hₙ are ∼400–600 Oe for flakes thinner than 100 nm and ∼600–900 Oe for 300–400 nm flakes, while the remanence ratio changes from nearly 100% to 0% after pressure treatment. Notably, the AFM-induced pressure modifies the magnetic behavior of the entire flake rather than only the directly stressed region. Raman spectroscopy further reveals a pressure-induced shift of up to ∼3 ± 0.5 cm⁻¹ in the E 2g phonon mode, suggesting possible vdW-gap deformation and altered interlayer coupling, while contributions from defect creation, layer sliding, or modified domain pinning dynamics cannot be fully excluded. These observations demonstrate localized tip-induced mechanical processing as an effective route for non-volatile magnetic domain engineering in 2D ferromagnets.