Shot Noise and “Universal” suppression factors

We present a review on some aspects of shot noise research, mainly focusing on our own work in the field, and on some conclusions that we can draw looking at the results obtained in the last few years. The activity on shot noise of one of us (M. M.) started during the preparation of his thesis, in 1986-1987, of which Lino was one of the advisors. That was the first exposure to the numerical simulation of noise phenomena, to shot noise, and to the effect on shot noise of the nanoscale size of devices. It was also an opportunity to realize how the application of numerical simulations could help gaining a better understanding of noise phenomena and, in particular, how it could help in the estimation of the limits of applicability of analytical models. This last issue will be the focal point of this paper, where we will try to summarize the results the we have obtained on the extent to which realistic devices and nanostructures can exhibit the shot noise suppression factors predicted on the basis of analytical models.