Shot Noise in Mesoscopic Transport Through Localised States

Abstract

We show that shot noise can be used for studies of hopping and resonant tunnelling between localised electron states. In hopping via several states, shot noise i s seen to be suppressed compared with its classical Poisson value SI = 2eI (I is the average current) and the suppression depends on the distribution of the barriers between the localised states. In resonant tunnell ing through a single impurity an enhancement of shot noise is observed. It has been established, both theore tically and experimentally, that a considerable increase of noise occurs due to Coulomb interaction between two resonant tunnelling channels.