Charge transport through weakly open one dimensional quantum wires

TL;DR

This paper studies how Coulomb interactions affect electron transport in finite-length quantum wires with weak coupling to leads, revealing step-like current-voltage behavior and conditions for Ohmic conductance.

Contribution

It provides a detailed analysis of resonant transmission in quantum wires considering Coulomb effects, highlighting the dependence on charging energy and level spacing.

Findings

Current-voltage curves show step-like features influenced by Coulomb interaction.

Near resonance, the $IV$ curve becomes Ohmic at low bias.

Conductance remains temperature-independent at large Coulomb energy and low temperatures.

Abstract

We consider resonant transmission through a finite-length quantum wire connected to leads via finite transparency junctions. The coherent electron transport is strongly modified by the Coulomb interaction. The low-temperature current-voltage ($IV$) curves show step-like dependence on the bias voltage determined by the distance between the quantum levels inside the conductor, the pattern being dependent on the ratio between the charging energy and level spacing. If the system is tuned close to the resonance condition by the gate voltage, the low-voltage $IV$ curve is Ohmic. At large Coulomb energy and low temperatures, the conductance is temperature-independent for any relationship between temperature, level spacing, and coupling between the wire and the leads.