Strictly One-Dimensional Electron System in Au Chains on Ge(001) Revealed By Photoelectron K-Space Mapping

TL;DR

This study uses photoelectron mapping to reveal that Au chains on Ge(001) form a strictly one-dimensional electron system, stable against Peierls distortion, with implications for low-dimensional physics research.

Contribution

It provides direct experimental evidence of strictly one-dimensional electron confinement in Au chains on Ge(001) using k-space photoemission mapping.

Findings

Observation of two metallic electron pockets with straight Fermi surface sheets

Confirmation of electrons confined to one dimension within experimental uncertainty

System remains stable against Peierls distortion down to 10 K

Abstract

Atomic nanowires formed by Au on Ge(001) are scrutinized for the band topology of the conduction electron system by k-resolved photoemission. Two metallic electron pockets are observed. Their Fermi surface sheets form straight lines without undulations perpendicular to the chains within experimental uncertainty. The electrons hence emerge as strictly confined to one dimension. Moreover, the system is stable against a Peierls distortion down to 10 K, lending itself for studies of the spectral function. Indications for unusually low spectral weight at the chemical potential are discussed.