PNNL

Abstract

We have produced erbium-doped germanium nanocrystals (NCs) using a new two cell physical vapor deposition system. Using element specific x-ray techniques (absorption and photoemission), we are able to probe the chemical environment of Er in the Ge NCs. Evidence for the optically active Er3+ state is seen at low Er concentrations, with a disruption of NC formation at high Er concentrations. The x-ray absorption measurements suggest that the Er occupies lattice sites near the surface of the NC. Analysis of the quantum confinement effect with Er doping suggests that the native quantum properties of the Ge NC are maintained at low Er concentrations.