High-detectivity infrared photodetector based on InAs submonolayer quantum dots grown on GaAs(001) with a 2 × 4 surface reconstruction

Abstract

The submonolayer quantum dots of an infrared photodetector were grown by molecular beam epitaxy in the presence of a very low As flux and a 2 × 4 surface reconstruction in order to effectively nucleate small two-dimensional InAs islands that are required to form such nanostructures. A specific detectivity of 9.2 × 1010 cm Hz1/2 W−1 was obtained at 10 K with a bias of 1.0 V.