Model study of adsorbed metallic quantum dots: Na on Cu(111)

TL;DR

This study models the electronic properties of Na quantum dots on Cu(111) using a 3D jellium approach, providing insights into their local density of states and comparison with STM data.

Contribution

It introduces a novel axially-symmetric jellium model that accounts for the first Na monolayer and Cu substrate effects, enabling large-scale simulations of metallic quantum dots.

Findings

Good agreement with STM $dI/dV$ spectra

Effective modeling of large Na adatom islands

Insights into local electronic structure

Abstract

We model electronic properties of the second monolayer Na adatom islands (quantum dots) on the Cu(111) surface covered homogeneously by the first Na monolayer. An axially-symmetric three-dimensional jellium model, taking into account the effects due to the first Na monolayer and the Cu substrate, has been developed. The electronic structure is solved within the local-density approximation of the density-functional theory using a real-space multigrid method. The model enables the study of systems consisting of thousands of Na-atoms. The results for the local density of states are compared with differential conductance ($dI/dV$) spectra and constant current topographs from Scanning Tunneling Microscopy.