Stark effect of the Au(111) and Cu(111) surface states

TL;DR

This study investigates the Stark effect on Au(111) and Cu(111) surface states using low-temperature scanning tunneling spectroscopy, confirming the tip-induced energy shift as a general phenomenon across different metal surfaces.

Contribution

It demonstrates the existence of a tip-induced Stark effect on Au(111) and Cu(111) surface states, supported by experimental data and model calculations, extending previous findings on Ag(111).

Findings

Binding energy increases as the tip approaches the surface.

The Stark effect is confirmed for Au(111) and Cu(111).

The effect is likely a general feature in scanning tunneling spectroscopy.

Abstract

We present a low-temperature scanning tunneling spectroscopy study of the Au(111) and of the Cu(111) surface states showing that their binding energy increases when the tip is approached towards the surface. This result, supported by a one-dimensional model calculation and by a comparison to existing photoemission spectroscopy measurements, confirms the existence of a tip-induced Stark effect as previously reported for Ag(111) [L. Limot et al., Phys. Rev. Lett. 91, 196801 (2003)], and suggests that this effect is a general feature of scanning tunneling spectroscopy.