Strain-Induced Robust Skyrmion Lattice at Room Temperature in van der Waals Ferromagnet.

Manipulating topological magnetic orders of 2D magnets by strain, once achieved, offers enormous potential for future low-power flexible spintronic applications. In this work, by placing Fe₃GaTe₂ (FGaT), a room-temperature 2D ferromagnet, on flexible substrate, a field-free and robust formation of skyrmion lattice induced by strain is demonstrated. By applying a minimal strain of ≈0.80% to pre-annealed FGaT flakes, the Magnetic Force Microscopy (MFM) tip directly triggers the transition from maze-like domains to an ordered skyrmion lattice while scanning the sample surface. The skyrmion lattice is rather stable against extensive cyclic mechanical testing (stretching, bending, and twisting over 2000 cycles each). It also exhibits stability across a wide range of magnetic fields (≈2.9 kOe) and temperatures (≈323 K), as well as long-term retention stability, highlighting its robustness and field-free stabilization. The strain effect reduces the lattice symmetry and enhances the Dzyaloshinskii-Moriya interaction (DMI) of FGaT, thus stabilizing the skyrmion lattice. The findings highlight the potential of FGaT for integrating magnetic skyrmions into future low-power-consumption flexible spintronics devices.