Atomically Precise Vacancy Lattices in Epitaxially Grown FeBr2 and CoBr2 on Au(111)

Abstract

The generation of extensive 2D periodic patterns of point defects in 2D materials, such as vacancy lattices, has been a challenging task until now. Here, we report on 2D transition metal dihalides grown epitaxially on Au(111) featuring periodically assembled halogen vacancies that result in alternating coordination of the transition metal ion and can function as antidot lattices. [1] Using low-temperature STM/ncAFM and LEED, we identified the structural properties of intrinsically patterned FeBr2 and CoBr2 monolayers grown epitaxially on Au(111). Density-functional theory indicates that Br-vacancies are favored due to low formation energies, and the formation of a vacancy lattice substantially reduces the lattice mismatch with the underlying Au(111). We demonstrate that interfacial strain engineering presents a versatile strategy for controlled patterning in 2D with atomic precision over several hundred nanometers to solve a longstanding challenge of growing atomically precise antidot lattices.[1] https://doi.org/10.48550/arXiv.2305.06489