Induced-charge distribution in vertical quantum dots

Abstract

We have studied the physical processes, which underlie the operation of a vertical quantum-dot nanodevice as a single- electron transistor. The Poisson-Schroedinger problem has been solved for the entire nanostructure. We have calculated the charge density on the quantum dot/gate electrode interface and the distribution of the ionized donors in n-GaAs layers close to the quantum-dot region. We have found that the characteristic rapid variation of the distribution of the ionized donors is responsible for the essential change of the electron confinement potential, which leads to a strong modification of the single- electron tunneling.