Sm cluster on hexagonal boron nitride supported by Ir(111): Formation of magnetic cluster superlattice Sm13@h-BN|Ir(111)

The goal toward the ultimate density limit of magnetic information storage is now focused on the creations of identical magnetic clusters as well as their arrangements on a template surface for obtaining an equidistant, monodisperse and equally oriented pattern. To achieve this goal, the combination of rare-earth (RE) cluster and specific template is a viable route, e.g., h-BN monolayer on Ir(111) surface within a corrugated moire structure (h-BN|Ir(111)) can act as a promising template to steer the intrinsically magnetic RE cluster in a well-defined orientation. Combining ab inito molecular dynamic (AIMD) simulation and spin-orbital coupling density function theory (DFT) calculations, we report that magnetic Sm-13 cluster can be stably deposited at the pore region of h-BN|Ir(111) template. The low-lying moire region potential of h-BN|Ir(111) template, stable icosahedron structure of Sm-13 cluster, and strong hybridization of Sm-5d6s orbitals with B/N-sp orbitals, play the synergetically roles to form Sm-13@h-BN|Ir(111) cluster superlattice. The local magnetic moments of Sm atoms in Sm-13 cluster are found to be robust against the structural configuration, localized site and inter-atom magnetic coupling, because their highly localized 4f states hybridize less with the spd states. Nevertheless, different deposition orientations and consequently the altered bonding interactions between Sm atoms and h-BN monolayer lead to different magnetic orders among Sm atoms. The appearances of large magnetic moment and giant magnetic anisotropy energy (MAE) of Sm-13 cluster as well as its high deposition stability render Sm-13@h-BN|Ir(111) for potential application of magnetic storage.

Automated summary

The study found that depositing magnetic Sm-13 clusters on a specific template can form a cluster superlattice with high magnetism, which can be used for magnetic storage.