Adatom generated spatially oscillating strain fields on isotropic and other substrates

TL;DR

This paper presents an elastic eigenvector approach to analyze how adatoms induce oscillating strain fields on isotropic substrates, revealing complex interaction patterns influenced by substrate elastic properties.

Contribution

The study introduces a method to model adatom-induced strain fields and their interactions, considering substrate elasticity and surface Brillouin zone effects, with comparisons between isotropic and anisotropic substrates.

Findings

Adatoms create quasi-circular strain rings affecting interactions.

Elastic constants influence the shape of strain fields.

Large short-distance attraction possible for certain adatom types.

Abstract

An extended elastic eigenvector approach for adatom interactions is applied to elastically isotropic substrates. The oscillating interactions between adatom monomers or dimers are caused by strain fields in the substrate. Expansive or contractive strain fields are surrounding adatoms in form of quasi circular rings. The exact shape of the ring structure depends on the elastic constants of the substrate and especially on the surface Brillouin zone. Interactions on isotropic substrates are depicted and compared with an anisotropic example. Overlays of 2-D plots can help to identify adatom structures caused by elastic effects and to prepare numerical calculations of their elastic energies. The consequences of different sorts of adatoms with different interaction sign are sketched, large short distance attraction could occur in such cases. Limitations of the method are discussed and possible applications are formulated.