Environmental Effects on the Local Density of States of CdSe Quantum Dots on a Au Substrate

Abstract

Scanning tunneling microscopy was used to image sub-monolay- er CdSe (d = 10 nm) quantum dots (QDs) on a gold substrate. After imaging the surface, scanning tunneling spectroscopy was performed on a single QD in the middle of a cluster, at the edge of a cluster and completely isolated from other QDs. Data showed that the zero-conductance region decreased with respect to the number of neighboring dots. A classical electrostatic screening model was used to analyze this effect.