Shot noise free conductance reduction in quantum wires

TL;DR

This paper demonstrates that in short interacting quantum wires, it is possible to achieve noiseless current with conductance reduced to e^2/h, without requiring spin-polarization, by analyzing exactly solvable models of impenetrable electrons.

Contribution

It introduces a theoretical model showing shot noise free conductance reduction in quantum wires without spin-polarization, using exactly solvable limits of the Coulomb Tonks gas.

Findings

Zero-temperature noiseless charge transport at conductance e^2/h

Conductance reduction below 2 e^2/h in short quantum wires

Validation within exactly solvable models of impenetrable electrons

Abstract

We show that a shot noise free current at conductance below 2 e^2/h is possible in short interacting quantum wires without spin-polarization. Our calculation is done for two exactly solvable limits of the ``Coulomb Tonks gas'', a one-dimensional gas of impenetrable electrons that can be realized in ultra-thin quantum wires. In both cases we find that charge transport through such a wire is noiseless at zero temperature while the conductance is reduced to e^2/h.