Is the regime with shot noise suppression by a factor 1/3 achievable in semiconductor devices with mesoscopic dimensions?

TL;DR

This paper investigates whether shot noise suppression by a factor of 1/3 can be achieved in mesoscopic semiconductor devices, concluding that it is challenging without macroscopic dimensions or mode-mixing mechanisms.

Contribution

The study provides numerical analysis showing the difficulty of reaching diffusive transport and shot noise suppression in mesoscopic semiconductor devices with potential disorder.

Findings

Achieving diffusive transport in mesoscopic devices is difficult without larger dimensions.

Mode-mixing mechanisms are necessary for diffusive behavior in one-dimensional disorder.

Shot noise suppression by a factor of 1/3 is unlikely in typical mesoscopic setups.

Abstract

We discuss the possibility of diffusive conduction and thus of suppression of shot noise by a factor 1/3 in mesoscopic semiconductor devices with two-dimensional and one-dimensional potential disorder, for which existing experimental results do not provide a conclusive result. On the basis of our numerical analysis, we conclude that it is quite difficult to achieve diffusive transport over a reasonably wide parameter range, unless the device dimensions are increased up to the macroscopic scale. In addition, in the case of one-dimensional disorder, some mechanism capable of mode-mixing has to be present in order to reach or even approach the diffusive regime.