Modeling of electronic properties of electrostatic quantum dots

Abstract

Electrostatic (gated) quantum dots are studied by computational methods. Electronic properties of the electrostatic quantum dots are determined by the confinement potential, which is created by external voltages, applied to the electrodes, and band offsets. We have solved the Poisson equation for the two-terminal quantum dot nanodevice made of several GaAs and AlGaAs layers and obtained the confinement potential profile in the entire nanodevice. We show how the confinement potential profile can be modeled, which allows us to design---to some extent---the required electronic properties of the nanodevice. The results have been confirmed by a good agreement with experimental data. We have discussed the similarities and differences between the two- and three-terminal quantum dot nanodevices studied experimentally by Ashoori et al. [Phys. Rev Lett. 71, 613 (1993)] and Tarucha et al. [Phys. Rev. Lett. 77, 3613 (1996)], respectively.