ABSTRACT
The fundamental physical principle underlying circuits including
single-electron tunneling (SET) junctions (called SET circuits) is
the Coulomb blockade, resulting from the quantization of charge,
and the associated phenomenon of Coulomb oscillations. The
basic physical phenomenon under consideration is the quantum
mechanical tunneling of electrons through a small insulating gap
between two metal leads. A single tunnel event can best be
understood as an electron sitting at both sides of the barrier at the same time, but the probability of finding the electron going from one side to the other is decreasing on one side of the barrier and
increasing on the other side during tunneling. As a consequence of
such a description charge is moved inside the tunneling junction.
