Laser-induced topological spin switching at room temperature in the van der Waals ferromagnet Fe3GaTe2

We demonstrate room-temperature nucleation and manipulation of topological spin textures in the van der Waals (vdW) ferromagnet Fe3GaTe2 using laser-pulse excitation. Rapid laser-induced heating followed by cooling enables access to the skyrmion bubble state at low fields and drives reversible switching between this state and labyrinth domains. The switching requires a minimum of about 20 pulses, and further reduction of the pulse number is limited by sample degradation at higher fluence. The nucleation occurs at magnetic induction fields as low as 5 mT, which substantially lowers the field requirement compared to slow field-cooling approaches. Micromagnetic simulations attribute this switching to the thermal cycle induced by the laser. Our findings establish vdW ferromagnets as promising candidates for room-temperature, laser-controlled, non-volatile memory storage applications.