Shot noise in parallel wires

TL;DR

This paper uses first-principles calculations to study shot noise in parallel carbon wires, revealing how interwire distance and bonding affect electron correlations and noise characteristics, with implications for nanoscale electronics.

Contribution

It provides the first detailed analysis of shot noise in parallel carbon wires, highlighting the sensitivity of Fano factor to interwire spacing and bonding.

Findings

Fano factor remains larger than single wire at small distances

Fano factor varies significantly with interwire spacing

Shot noise effectively probes electron correlations in nanoscale conductors

Abstract

We report first-principles calculations of shot noise properties of parallel carbon wires in the regime in which the interwire distance is much smaller than the inelastic mean free path. We find that, with increasing interwire distance, the current approaches rapidly a value close to twice the current of each wire, while the Fano factor, for the same distances, is still larger than the Fano factor of a single wire. This enhanced Fano factor is the signature of the correlation between electron waves traveling along the two different wires. In addition, we find that the Fano factor is very sensitive to bonding between the wires, and can vary by orders of magnitudes by changing the interwire spacing by less than 0.5 \AA. While these findings confirm that shot noise is a very sensitive tool to probe electron transport properties in nanoscale conductors, they also suggest that a considerable experimental control of these structures is required to employ them in electronics.