Fano factor reduction on the 0.7 structure in a ballistic one-dimensional wire

TL;DR

This study investigates the 0.7 conductance anomaly in a ballistic 1D wire by measuring current noise, revealing it is linked to two conduction channels with different transmission probabilities, and showing the Fano factor reduction and its magnetic field dependence.

Contribution

The paper provides experimental evidence connecting the 0.7 structure to two conduction channels with distinct transmissions, advancing understanding of this conductance anomaly.

Findings

Fano factor reduces at the 0.7 conductance plateau

Fano factor vanishes under strong magnetic field

Evidence for two conduction channels with different transmission probabilities

Abstract

We have measured the non-equilibrium current noise in a ballisticone-dimensional wire which exhibits an additional conductanceplateau at $0.7\times2e^2/h$. The Fano factor shows a clearreduction on the 0.7 structure, and eventually vanishes uponapplying a strong parallel magnetic field. These results provideexperimental evidence that the 0.7 structure is associated withtwo conduction channels which have different transmissionprobabilities.