Band structure effects on the Be(0001) acoustic-surface-plasmon energy dispersion

TL;DR

This study uses first-principles calculations to analyze the anisotropic dispersion of acoustic surface plasmons on Be(0001), revealing their potential to probe the surface's electron-hole excitation spectrum.

Contribution

It provides the first detailed theoretical analysis of surface plasmon dispersion on Be(0001) using many-body theory, highlighting anisotropy and experimental mapping potential.

Findings

Significant anisotropy in plasmon dispersion along different directions.

Plasmons can be used to map the Shockley surface state band.

First-principles calculations align with experimental measurement capabilities.

Abstract

We report first-principles calculations of acoustic surface plasmons on the (0001) surface of Be, as obtained in the random-phase approximation of many-body theory. The energy dispersion of these collective excitations has been obtained along two symmetry directions. Our results show a considerable anisotropy of acoustic surface plasmons, and underline the capability of experimental measurements of these plasmons to {\it map} the electron-hole excitation spectrum of the quasi two-dimensional Shockley surface state band that is present on the Be(0001) surface.