Optical and magnetic properties for erbium-related centres in self-assembly silicon nanostructures

We present the first findings of a highly efficient Er3+-related electrolum inescence (I-4(13/2)) --> (I-4(15/2)) from self-assembly silicon nanostruct ures with sizes varying from 1.0 to 10 nm that are naturally formed as a su bsequence of quantum-size n(+)-p junctions. The built-in electric field ind uced by these n(+)-p junctions is found to result in the Stark effect that perturbs strong sp-f mixing due to the electron-hole localization on the Er 3+ ions incorporated into nanostructures. This spatial confinement is shown to cause ultrafast energy transfer to the erbium-related centres which inc reases with decreasing size of nanostructures thereby enhancing the electro luminescent efficiency. (C) 1999 Elsevier Science B.V. All rights reserved.