Description
This poster presents our investigation of how spin spirals in few-layer NiI₂ can be tuned by thickness and curvature. Using layer-by-layer growth and spin-polarized STM, we directly visualize helical spin textures from 1–7 monolayers and show that the spiral wavelength increases while the wavevector rotates, revealing a dimensional crossover driven by interlayer exchange. Beyond this global thickness control, local wrinkles and substrate steps bend the spirals, demonstrating curvature-induced magneto-elastic coupling. Analytical spin modeling and SpinGNN++ spin-lattice simulations connect these observations to changes in exchange and Kitaev interactions. Together, the results establish thickness and strain as practical knobs for engineering multiferroic spin textures.
这张海报介绍了我们如何利用厚度和曲率调控少层 NiI₂ 中的螺旋自旋结构。通过逐层生长与自旋极化 STM，我们直接观测到 1–7 层 NiI₂ 中自旋螺旋波长和波矢方向的连续演化，揭示了由层间交换相互作用驱动的维度交叉行为。同时，局域褶皱和衬底台阶会使自旋条纹发生偏转，说明曲率可通过磁弹耦合改变局域交换相互作用。结合解析自旋模型和 SpinGNN++ 自旋-晶格模拟，该工作表明厚度和应变是调控范德华多铁磁性自旋纹理的两个有效自由度。
