First-principles Green's-function method for surface calculations: a pseudopotential localized basis set approach

TL;DR

This paper introduces an efficient surface Green's-function method within density functional theory using a pseudopotential localized basis set, enabling accurate modeling of semi-infinite surfaces and overcoming slab method limitations.

Contribution

The paper presents a novel implementation of a surface Green's-function approach for atomistic surface modeling within DFT, improving accuracy and versatility over traditional slab methods.

Findings

Accurate metal work function calculations

Effective band alignment in semiconductor heterostructures

Proper modeling of surface states in metals and topological insulators

Abstract

We present an efficient implementation of a surface Green's-function method for atomistic modeling of surfaces within the framework of density functional theory using a pseudopotential localized basis set approach. In this method, the system is described as a truly semi-infinite solid with a surface region coupled to an electron reservoir, thereby overcoming several fundamental drawbacks of the traditional slab approach. The versatility of the method is demonstrated with several applications to surface physics and chemistry problems that are inherently difficult to address properly with the slab method, including metal work function calculations, band alignment in thin-film semiconductor heterostructures, surface states in metals and topological insulators, and surfaces in external electrical fields. Results obtained with the surface Green's-function method are compared to experimental measurements and slab calculations to demonstrate the accuracy of the approach.