AI 中文总结
研究单层NiI₂靠近超导NbSe₂衬底时磁基态的变化，利用低温STM和STS，发现金属衬底使NiI₂交换作用重整化并驱动其进入铁磁基态，确立YSR态为二维磁性原位探针，证明衬底工程可控制原子级薄材料磁序。
AI 中文摘要
非共线自旋纹理和强自旋轨道相互作用产生的多铁性为单层极限下的磁电功能提供了一条途径。虽然理论预测单层多铁性材料的性质可通过应变、门电压或近邻效应调节，但此类控制的实验证明仍很稀少。本文表明，二维多铁性原型单层NiI₂的磁基态会因靠近超导NbSe₂衬底而改变。利用低温扫描隧道显微镜（STM）和能谱（STS），我们发现金属衬底使NiI₂内的交换相互作用重整化，并将其驱动到铁磁基态。这可通过探测NbSe₂衬底超导能隙内的汤川-芝-鲁西诺夫（YSR）态来可视化。我们的结果确立了YSR态作为二维磁性的原位探针，并证明衬底工程是控制原子级薄材料中磁序的一种手段。
英文摘要
Multiferroicity arising from non-collinear spin textures and strong spin-orbit interactions offers a route to magnetoelectric functionality in the monolayer limit. Although theory predicts that the properties of monolayer multiferroics can be tuned by strain, gating, or proximity effects, experimental demonstrations of such control remain scarce. Here we show that the magnetic ground state of monolayer NiI$_2$, a prototypical two-dimensional multiferroic, is altered by proximity to a superconducting NbSe$_2$ substrate. Using low-temperature scanning tunnelling microscopy (STM) and spectroscopy (STS), we show that the metallic substrate renormalizes the exchange interactions within NiI$_2$ and drives it into a ferromagnetic ground state. This can be visualized by probing the Yu-Shiba-Rusinov (YSR) states within the superconducting gap of the NbSe$_2$ substrate. Our results establish YSR states as an in situ probe of two-dimensional magnetism and demonstrate substrate engineering as a means of controlling magnetic order in atomically thin materials.
