Shot noise suppression in quasi one-dimensional Field Effect Transistors

TL;DR

This paper introduces a new statistical method to evaluate shot noise in quasi-1D FETs, explicitly accounting for Coulomb and Pauli effects, and demonstrates significant noise reduction in simulations.

Contribution

It extends the Landauer-Buttiker approach by including Coulomb interactions, providing a more accurate noise evaluation method for nano-scale transistors.

Findings

Shot noise reduced to 23% of full noise in strong inversion.

Neglecting Coulomb effects overestimates noise by up to 180%.

Method implemented with NEGF and Monte Carlo simulations.

Abstract

We present a novel method for the evaluation of shot noise in quasi one-dimensional field-effect transistors, such as those based on carbon nanotubes and silicon nanowires. The method is derived by using a statistical approach within the second quantization formalism and allows to include both the effects of Pauli exclusion and Coulomb repulsion among charge carriers. In this way it extends Landauer-Buttiker approach by explicitly including the effect of Coulomb repulsion on noise. We implement the method through the self-consistent solution of the 3D Poisson and transport equations within the NEGF framework and a Monte Carlo procedure for populating injected electron states. We show that the combined effect of Pauli and Coulomb interactions reduces shot noise in strong inversion down to 23 % of the full shot noise for a gate overdrive of 0.4 V, and that neglecting the effect of Coulomb repulsion would lead to an overestimation of noise up to 180 %.