Scaling Quantum Dot Light-Emitting Diodes to Submicrometer Sizes

We introduce a device structure and a fabrication technique that allow the realization of efficient light-emitting diodes (LEDs) with dimensions of the active area in the »100 nm range. Using optical lithography, selective oxidation, and an active region consisting of InAs quantum dots (QDs), we fabricated LEDs with light-current-voltage characteristics which scale well with nominal device area down to 600 nm-diameters at room temperature. The scaling behaviour provides evidence for strong carrier confinement in the QDs and shows the potential for the realization of high-efficiency single-photon LEDs operating at room temperature