Speaker
Description
This study demonstrates the localized creation of skyrmions (SKs) in the two-dimensional ($2$D) ferromagnetic material Fe$_3$GaTe$_2$ using conductive atomic force microscopy (cAFM). By applying bias voltage through the cAFM tip, sufficient current is generated to induce localized Joule heating, transforming random stripe domains into bubble domains. SKs were successfully induced under ambient conditions and remained stable at room temperature, as confirmed by magnetic force microscopy (MFM). For Fe$_3$GaTe$_2$ layers with thicknesses of $1$ $\mu m$, $200$ nm, and $100$ nm, the average diameters of bubble domains were measured at $620\pm 100$ nm, $325 \pm 80$ nm, and $230 \pm 70$ nm, respectively, approximately $20\%$ larger than the pristine stripe width. By optimizing parameters such as bias voltage, application duration, and tip temperature based on Fe$_3$GaTe$_2$ thickness, the induced SK density could be precisely controlled, ranging from few SKs within areas $<5\mu m^{2}$ to nearly $10^4$ SKs within $1200$ $\mu m^{2}$. Furthermore, multi-point triggering demonstrated the re-writability of the domain structures, with non-overlapping domains remaining unaffected. These findings offer critical insights into the tunability of magnetic textures in $2$D ferromagnets, providing a foundation for developing next-generation spintronic devices based on $2$D heterostructures.
