Creating and modulating electronic states on noble metal surfaces: ultrathin Ag islands on Si(111)-7$\times$7 as a prototype

TL;DR

This study demonstrates how ultrathin silver islands on Si(111)-7x7 surfaces exhibit tunable electronic states due to hybridization effects at the interface, with potential implications for surface electronic engineering.

Contribution

It introduces a method to create and modulate electronic states on noble metal surfaces through controlled island thickness and hybridization effects.

Findings

Electronic state at -0.40 to -0.15 eV observed on thin Ag islands

Hybridization strength depends on Ag island thickness

Modulation of surface electronic states achieved by controlling island thickness

Abstract

Various-thickness Ag islands were prepared on Si(111)-7$\times$7 using the one-step deposition at a high substrate temperature. An electronic state centered at -0.40$\sim$-0.15eV versus E$_{Fermi}$, detectable on the surface of the Ag islands thinner than 9 layers, was created by the electronic hybridization between Ag and Si at the Ag-Si interface. Scanning tunneling microscopy/spectroscopy and density functional theory revealed that the thickness of Ag islands determined the strength of the hybridization, leading to a modulation to the energy and intensity of the state on the surface.