Magnetoelectric subbands and eigenstates in the presence of Rashba and Drresselhaus spin orbit interactions in a quantum wire

TL;DR

This paper derives the eigenenergies and eigenstates of electrons in a quantum wire with Rashba and Dresselhaus spin-orbit interactions under various magnetic field orientations, revealing non-parabolic dispersions and wavevector-dependent spin polarization.

Contribution

It provides a comprehensive analysis of magnetoelectric subbands and eigenstates considering combined Rashba and Dresselhaus effects in different magnetic field orientations.

Findings

Eigenenergies are non-parabolic and asymmetric in most cases.

Spin polarization depends on the wavevector and lacks a fixed quantization axis.

Dispersion relations vary significantly with magnetic field orientation.

Abstract

We derive the eigenenergies and eigenstates of electrons in a quantum wire subjected to an external magnetic field. These are calculated in the presence of spin orbit interactions arising from the Rashba (structural inversion asymmetry) and Dresselhaus (bulk inversion asymmetry) effects. We consider three cases: the external magnetic field is oriented (i) along the axis of the wire, (ii) perpendicular to the axis but parallel to the electric field associated with structural inversion asymmetry (Rashba effect), and (iii) perpendicular to the axis as well as the electric field. In all cases, the dispersions of the eigenenergies are non-parabolic and the subbands do not have a fixed spin quantization axis (meaning that the spin polarization of the electron is wavevector dependent). Except in the second case, the dispersion diagrams are also, in general, asymmetric about the energy axis.