Transport measurements through stacked InAs self-assembled quantum dots in time domain

Abstract

We report electronic characterization of stacked InAs self-assembled quantum dots (SAQDs) embedded in GaAs, usingultra-short pulses. Electrical pulse trains with the width ranging from 50 to 500 ps were applied on the waveguide-typetop electrode and the average substrate current was monitored. The current showed staircases and oscillatory features as afunction of the pulse width. The staircase could represent single electron injection into SAQDs and the observed oscillatoryfeatures could be related with temporal change of electronic occupation in quantum states of SAQDs.