Universality of the 1/3 shot-noise suppression factor in nondegenerate diffusive conductors

TL;DR

This paper demonstrates that in nondegenerate diffusive conductors, shot-noise is universally suppressed to one-third of its Poissonian value under specific conditions, highlighting the role of Coulomb interactions and device parameters.

Contribution

It establishes the universality of the 1/3 shot-noise suppression factor in nondegenerate diffusive conductors through Monte Carlo simulations under defined conditions.

Findings

The 1/3 suppression factor is universal in elastic collision regimes.

Long-range Coulomb interactions are essential for shot-noise suppression.

Suppression occurs when voltage is high and device length exceeds mean free path and Debye length.

Abstract

Shot-noise suppression is investigated in nondegenerate diffusive conductors by means of an ensemble Monte Carlo simulator. The universal 1/3 suppression value is obtained when transport occurs under elastic collision regime provided the following conditions are satisfied: (i) The applied voltage is much larger than the thermal value; (ii) the length of the device is much longer than both the elastic mean free path and the Debye length. By fully suppressing carrier-number fluctuations, long range Coulomb interaction is essential to obtain the 1/3 value in the low-frequency limit.