Noise influence on electron dynamics in semiconductors driven by a periodic electric field

TL;DR

This study investigates how adding correlated external noise to a high-frequency electric field can reduce electron velocity fluctuations in low-doped GaAs semiconductors, revealing nonlinear effects and potential noise reduction strategies.

Contribution

It extends previous theories by analyzing noise-induced effects on electron transport under cyclostationary conditions using Monte Carlo simulations.

Findings

External correlated noise can reduce total electron velocity fluctuation noise.

Spectral density of velocity fluctuations shows nonlinear dependence on noise intensity.

Optimal noise correlation times enhance constructive noise effects.

Abstract

Studies about the constructive aspects of noise and fluctuations in different non-linear systems have shown that the addition of external noise to systems with an intrinsic noise may result in a less noisy response. Recently, the possibility to reduce the diffusion noise in semiconductor bulk materials by adding a random fluctuating contribution to the driving static electric field has been tested. The present work extends the previous theories by considering the noise-induced effects on the electron transport dynamics in low-doped n-type GaAs samples driven by a high-frequency periodic electric field (cyclostationary conditions). By means of Monte Carlo simulations, we calculate the changes in the spectral density of the electron velocity fluctuations caused by the addition of an external correlated noise source. The results reported in this paper confirm that, under specific conditions, the presence of a fluctuating component added to an oscillating electric field can reduce the total noise power. Furthermore, we find a nonlinear behaviour of the spectral density with the noise intensity. Our study reveals that, critically depending on the external noise correlation time, the dynamical response of electrons driven by a periodic electric field receives a benefit by the constructive interplay between the fluctuating field and the intrinsic noise of the system.