Exciton Recombination in Self-Assembled InAs/GaAs Small Quantum Dots under an External Electric Field

Abstract

The effects of an external electric field on the photoluminescence of small self-assembled InAs/GaAs quantum dots (3–4 nm high) have been studied at different temperatures, laser power, and laser wavelength excitation. The shallow nature of the only confined electron level is revealed by the strong photocurrent signal measured at low temperatures. In this QD system, recombination from that electron level with ground and first excited hole states can be observed in high power excited PL and low power excited PL under direct applied bias, when the hole population is high enough under these conditions.