Thermal Noise at Quasi-equilibrium

TL;DR

This paper derives a universal expression linking thermal current fluctuations to voltage characteristics in quasi-equilibrium networks, with applications to p-n junctions and field-effect transistors.

Contribution

It introduces a new theoretical framework connecting thermal noise power to device characteristics at quasi-equilibrium, including predictions for transistors and diodes.

Findings

Thermal noise power closely matches equilibrium values.

Derived noise expressions for ideal p-n junctions.

Predicted shot noise suppression in diodes.

Abstract

An expression that relates thermal current fluctuations in two terminal networks at quasi-equilibrium to their current voltage characteristics is presented. It is based upon the observation that the available thermal noise power at quasi-equilibrium is very close to the equilibrium value. As an example, current noise in ideal p-n junctions is obtained from their characteristics. Thermal current noise in field effect transistors is predicted by this approach, as well as "shot noise suppression" due to barrier lowering in solid-state diodes.