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

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