Modelling and design of quantum dot cellular automata

Research aimed at design of electronic computers that contain nano-size components has been developing very rapidly. In this work we study the quantum dot cellular automata (QCA) by the full Schrodinger equation in which the antisymmetric property of the many-electron state is included. We have concluded that because of the quantum wave characteristics, a localized electronic state appears only at very high gate voltages in a dual-gate Si quantum dot structure. The Coulomb exchange interaction due to the wave function overlapping between two electrons reduces the total energy of the electron pair. These two factors must be carefully studied for a functional QCA. (C) 1998 American Institute of Physics.