Spin freezing by Anderson localization in one-dimensional semiconductors

TL;DR

This paper investigates how strong disorder in one-dimensional semiconductor nanowires causes spin localization due to Anderson localization, enabling long-term spin polarization control via spin-orbit interaction.

Contribution

It demonstrates the universal effect of Anderson localization on spin dynamics in disordered nanowires and its impact on spin polarization stability.

Findings

Spin density reaches a plateau after short relaxation in strong disorder.

Long-term spin polarization can be tuned by spin-orbit interaction.

Localization effect depends universally on disorder and spin-orbit strength.

Abstract

One-dimensional quantum wires are considered as prospective elements for spin transport and manipulation in spintronics. We study spin dynamics in semiconductor GaAs-like nanowires with disorder and spin-orbit interaction by using a rotation in the spin subspace gauging away the spin-orbit field. If the disorder is sufficiently strong, the spin density after a relatively short relaxation time reaches a plateau. This effect is a manifestation of the Anderson localization and depends in a universal way on the disorder and the spin-orbit coupling strength. As a result, at a given disorder, semiconductor nanowires can permit a long-term spin polarization tunable with the spin-orbit interactions.