Resonant reflection of interacting electrons from an impurity in a quantum wire: interplay of Zeeman and spin-orbit effects

TL;DR

This paper investigates how a weak spin-orbit coupling and Zeeman effects influence resonant electron reflection in a quantum wire with an impurity, revealing complex tunneling behavior and interaction-induced profile modifications.

Contribution

It introduces a detailed analysis of resonant reflection in a quantum wire considering electron-electron interactions and spin effects, highlighting the emergence of a two-peak reflection profile.

Findings

Complete transport blockade near the impurity level due to resonant reflection

Two-peak structure in the reflection profile caused by electron interactions and Friedel oscillations

Interaction effects significantly modify the shape of the resonant reflection

Abstract

A single-channel quantum wire with two well-separated Zeeman subbands and in the presence of a weak spin-orbit coupling is considered. An impurity level which is split off the upper subband is degenerate with the continuum of the lower subband. We show that, when the Fermi level lies in the vicinity of the impurity level, the transport is completely blocked. This is the manifestation of the effect of resonant reflection and can be viewed as resonant tunneling between left-moving and right-moving electrons via the impurity level. We incorporate electron-electron interactions and study their effect on the shape of the resonant-reflection profile. This profile becomes a two-peak structure, where one peak is caused by resonant reflection itself, while the origin of the other peak is reflection from the Friedel oscillations of the electron density surrounding the impurity.