Spin-dependent transport of electrons in the presence of smooth lateral barrier and spin-orbit interaction

TL;DR

This paper theoretically investigates how spin-orbit interaction influences electron reflection in two-dimensional systems with lateral barriers, revealing potential for spin filtering and analyzing different regimes of spin conversion efficiency.

Contribution

It introduces a detailed theoretical analysis of multi-beam electron reflection with spin-orbit effects in lateral barriers, highlighting conditions for effective spin filtering in nano-structures.

Findings

Spin conversion remains strong in realistic nano-structures.

Smooth barriers can reduce spin conversion efficiency.

Adiabatic behavior occurs with very strong spin-orbit interaction.

Abstract

We describe theoretically the process of multi-beam reflection in a two-dimensional electron system with a lateral potential barrier. Due to spin-orbital interaction, the reflection process leads to the formation of three beams with different spin polarizations. The efficiency of spin conversion can become small for smooth lateral barriers. Nevertheless, we demonstrate that the spin-conversion effect remains strong for realistic lithographical potentials and spin-orbit interactions in etched lateral nano-structures. The system with a lateral barrier suggests useful applications as a spin-filtering device. The expected quasi-classical adiabatic behavior without spin conversion is found in the system with a very strong spin-orbit interaction. We also consider the quasi-classical motion of electrons in a system with boundaries in a magnetic field and two magnetic focusing geometries.