Theory of spin noise in nanowires

TL;DR

This paper develops a theoretical framework for understanding spin noise in semiconductor nanowires, highlighting slow spin relaxation and a diverging noise spectrum at low frequencies, which benefits spin-noise spectroscopy.

Contribution

It introduces a novel theory accounting for random spin-orbit coupling in nanowires and analyzes its impact on spin relaxation and noise spectra.

Findings

Spin relaxation can be very slow in nanowires.

Noise power spectrum increases algebraically as frequency approaches zero.

Nanowires are ideal for spin-noise spectroscopy studies.

Abstract

We develop a theory of spin noise in semiconductor nanowires considered as prospective elements for spintronics. In these structures spin-orbit coupling can be realized as a random function of coordinate correlated on the spatial scale of the order of 10 nm. By analyzing different regimes of electron transport and spin dynamics, we demonstrate that the spin relaxation can be very slow and the resulting noise power spectrum increases algebraically as frequency goes to zero. This effect makes spin effects in nanowires best suitable for studies by rapidly developing spin-noise spectroscopy.