Abstract：
Patterning and defect engineering are key methods for tuning the properties and enabling distinctive functionalities in two-dimensional (2D) materials. However, generating 2D periodic patterns of point defects in 2D materials, such as vacancy lattices that can serve as antidot lattices, has been elusive until now. Herein, we report on 2D transition metal dihalides epitaxially grown on metal surfaces featuring periodically assembled halogen vacancies that result in alternating coordination of the transition metal atom. Using low-temperature scanning probe microscopy and low-energy electron diffraction, we identified the structural properties of intrinsically patterned FeBr2 and CoBr2 monolayers grown epitaxially on Au(111). Density functional theory reveals that Br vacancies are facilitated by low formation energies, and the formation of a vacancy lattice results in a substantial decrease in the lattice mismatch with the underlying Au(111). We demonstrate that interfacial strain engineering presents a versatile strategy for controlled patterning in two dimensions with atomic precision over several hundred nanometers to solve a long-standing challenge of growing atomically precise antidot lattices. In particular, patterning of 2D materials containing transition metals provides a versatile method to achieve unconventional spin textures with noncollinear spin.
摘要：
图案化和缺陷工程是用于调整二维(2D)材料中的性质和实现独特功能的关键方法。然而,在2D材料中生成点缺陷的2D周期性图案，例如可以用作对点晶格的空位晶格，直到现在都难以捉摸。在这里，我们报告了在金属表面上外延生长的2D过渡金属二卤化物，其特征是周期性组装的卤素空位导致过渡金属原子的交替配位。利用低温扫描探针显微镜和低能电子衍射,我们确定了在Au（111）上外延生长的固有图案化FeBr2和CoBr2单层的结构特性。密度泛函理论表明，低形成能促进Br空位，空位晶格的形成导致与底层Au(111)的晶格失配显著减少。我们证明了界面应变工程提出了一种通用的策略，用于在二维上控制图案化，原子精度超过数百纳米，以解决生长原子精确反点晶格的长期挑战。特别是,包含过渡金属的2D材料的图案化提供了一种通用的方法来实现具有非共线自旋的非常规自旋纹理。
