ABSTRACT
In the previous chapters, a single tunnel junction in a Coulomb
blockade was modeled essentially as a charged (or charging)
capacitor. Single-electron tunneling as a Dirac delta pulse can
be extended to more junctions. Therefore, consider a two-tunnel
junction circuit in a Coulomb blockade. The two capacitors create
an island in the circuit, that is, a part of the circuit between the two
capacitors is electrically isolated from the circuit. If we allow the
possibility that one or more electrons had been tunneled through
only one of the junctions then the total net charge of the island and
its environment will be nonzero and opposite.
