Magnetic domain modulation in van der Waals material Fe₃GaTe₂ via external magnetic field

Microscopic spin-textures in two-dimensional van der Waals (vdW) ferromagnets, particularly Fe₃GaTe₂ (FGaT), offer strong potential for spintronic applications due to their high Curie temperature, stable perpendicular magnetic anisotropy, and the critical importance of controllable magnetic properties. FGaT crystals with thicknesses ranging from 150 nm to 2 μm exhibit robust stripe, bubble, and complex magnetic textures during field cooling, with domain size systematically increasing with cooling-field strength. The resulting bubble and mixed-domain states remain stable above 2000 Oe at room temperature, reflecting the intrinsic stability of vdW-mediated spin textures. External magnetic fields tune bubble size through reversible expansion or contraction, and hexagonal bubble ordering emerges through field-induced splitting and shape transformations. Domain annihilation and merging processes are also observed. Micromagnetic simulations reproduce the field-driven evolution and reveal size- and time-dependent dynamics consistent with experiment. These findings provide critical insights into the field-tunable magnetic behavior of FGaT and highlight its potential in spintronic applications, particularly for domain manipulation and corresponding spin transport properties.