Shot-noise suppression in multimode ballistic Fermi conductors

We have derived a general formula describing current noise in multimode bal listic channels connecting source and drain electrodes with Fermi electron gas. In particular (at eV much greater than k(B)T), the expression describe s the nonequilibrium "shot" noise, which may be suppressed by both Fermi co rrelations and space charge screening. The general formula has been applied to an approximate model of a two-dimensional nanoscale, ballistic, metal-o xide-semiconductor field-effect transistor. At large negative gate voltages , when the density of electrons in the channel is small, shot noise spectra l density S-I(0) approaches the Schottky value 2eI, where I is the average current. However, at positive gate voltages, when the maximum potential ene rgy in the channel is below the Fermi level of the electron source, the noi se can be at least an order of magnitude smaller than the Schottky value, m ostly due to Fermi effects. [S0163-1829(99)50228-2].