Effects of Coulomb interaction and tunneling on electron transport in coupled one-dimensional systems: from ballistic to diffusive regime

TL;DR

This paper develops a linear theory for electron transport in coupled quantum wires, analyzing how Coulomb interaction and tunneling influence resistance behavior across ballistic and diffusive regimes, including interference effects.

Contribution

It introduces a comprehensive model that accounts for Coulomb interaction, tunneling, and phonon effects in coupled quantum wires, valid in both transport regimes.

Findings

Negative transresistance in ballistic regime due to tunneling and Coulomb drag.

Opposition of tunneling to Coulomb drag in diffusive regime, leading to positive transresistance.

Interference oscillations in resistance damped exponentially with wire length.

Abstract

A linear theory of electron transport is developed for a system of two ideal quantum wires, of length L, coupled by tunneling and Coulomb interaction. The interaction of electrons with acoustical phonons is included and the results are valid in both the ballistic and diffusive regime. In the {\it ballistic} regime, both tunneling and Coulomb drag lead to a {\it negative} transresistance R_{TR}, while in the {\it diffusive} regime the tunneling opposes the drag and leads to a {\it positive} R_{TR}. If L is smaller than the phase-breaking length, the tunneling leads to interference oscillations of the resistance that are damped exponentially with L.