Single-electron charging and coulomb interaction in InAs self-assembled quantum dot arrays

Sequential single-electron charging is observed in InAs self-assembled quantum dots using capacitance spectroscopy. In this system, the Coulomb energy is smaller than the interlevel energy spacings due to the quantum confinement and both effects can be separately identified. A theoretical model is proposed for this system and the capacitance experiments were devised in order to experimentally observe the effects of Coulomb interaction between electrons on the dots. The effects of inter- and intradot Coulomb interaction have been observed in the capacitance spectra. A good agreement between the proposed model and experiment is achieved.