Deviation from Fermi-liquid behavior in two-dimensional surface states of Au-induced nanowires on Ge(001) by correlation and localization

TL;DR

This study investigates the electronic surface states of Au-induced nanowires on Ge(001), revealing deviations from Fermi-liquid behavior due to correlation and localization effects in these two-dimensional metallic states.

Contribution

It provides the first detailed ARPES analysis showing how disorder-induced correlation effects cause non-Fermi-liquid behavior in these nanowire surface states.

Findings

Identification of closed Fermi surfaces indicating 2D surface states

Observation of suppressed photoelectron intensity near Fermi energy

Attribution of suppression to correlation and localization effects

Abstract

The electronic states of Au-induced atomic nanowires on Ge(001) (Au/Ge(001) NWs) have been investigated by angle-resolved photoelectron spectroscopy with linearly polarized light. We have found three electron pockets around $\bar{J}\bar{K}$, where the Fermi surfaces are closed in a surface Brillouin zone, indicating that the surface states of Au/Ge(001) NWs are two-dimensional whereas the atomic structure is one-dimensional. The two-dimensional metallic states exhibit remarkable suppression of the photoelectron intensity near a Fermi energy. This suppression can be explained by the correlation and localization effects in disordered metals, which is a deviation from a Fermi-liquid model.