Effect of the spin-orbit interaction on the band structure and conductance of quasi-one-dimensional systems

TL;DR

This paper investigates how spin-orbit interaction influences the band structure and conductance in quasi-one-dimensional electron systems, revealing complex effects like subband minima and anticrossings due to potential confinements.

Contribution

It introduces a detailed model showing the significant impact of Rashba and parabolic confinements on subband energies and wave functions in 2DEG-based systems.

Findings

Spin-orbit interaction causes wave vector dependence in subband energies.

Additional subband minima are induced by the combined effects of confinements.

Anticrossings between subbands are observed due to symmetry considerations.

Abstract

We discuss the effect of the spin-orbit interaction on the band structure, wave functions and low temperature conductance of long quasi-one-dimensional electron systems patterned in two-dimensional electron gases (2DEG). Our model for these systems consists of a linear (Rashba) potential confinement in the direction perpendicular to the 2DEG and a parabolic confinement transverse to the 2DEG. We find that these two terms can significantly affect the band structure introducing a wave vector dependence to subband energies, producing additional subband minima and inducing anticrossings between subbands. We discuss the origin of these effects in the symmetries of the subband wave functions.