EFFECT OF THE ELECTROMAGNETIC ENVIRONMENT ON COULOMB-BLOCKADE DEVICES- MODEL, EXPERIMENTS, AND METHOD OF ANALYSIS

The effect of the electromagnetic environment on Coulomb blockade devi ces can be estimated through a simple horizon model where the interact ion length is determined by the Heisenberg uncertainty principle. The advantage of this horizon model can be demonstrated in a device with t wo tunnel junctions in parallel where a cutoff voltage related to phys ical dimensions is observed. This model also explains the characterist ics of single junctions and single-electron tunneling (SET) transistor s. Several Al/AlOx/Al devices of various geometries were measured and the effective Coulomb barrier has been investigated through the offset voltage defined as V-off = V-IdV/dI. We have also used V-off to deter mine the capacitances of SET transistors, from which we determined mic rostrip capacitance as a function of island size.