Effect of dielectric confinement on energetics of quantum metal films

TL;DR

This paper presents a self-consistent method to analyze how dielectric environments influence the electronic properties of metal films, revealing that dielectric asymmetry reduces work function and surface energy.

Contribution

It introduces a modified Kohn-Sham approach combined with the stabilized jellium model for asymmetric metal-dielectric systems, providing new insights into their energetics.

Findings

Dielectric environment decreases electron work function and surface energy.

Change in work function depends on the average dielectric constant of both sides.

Method applied to Na, Al, and Pb films with consistent results.

Abstract

We suggest a method for the self-consistent calculations of characteristics of metal films in dielectric environment. Within a modified Kohn-Sham method and stabilized jellium model, the most interesting case of asymmetric metal-dielectric sandwiches is considered, for which dielectric media are different from the two sides of the film. As an example, we focus on Na, Al and Pb. We calculate the spectrum, electron work function, and surface energy of polycrystalline and crystalline films placed into passive isolators. We find that a dielectric environment generally leads to the decrease of both the electron work function and surface energy. It is revealed that the change of the work function is determined only by the average of dielectric constants from both sides of the film.