Infinite spin diffusion length of any spin polarization along direction perpendicular to effective magnetic field from Dresselhaus and Rashba spin-orbit couplings with identical strengths in (001) GaAs quantum wells

TL;DR

This paper discusses how recent experiments support the theoretical prediction that spin polarization perpendicular to the effective magnetic field in certain GaAs quantum wells can have an infinite diffusion length due to specific spin-orbit coupling conditions.

Contribution

It provides experimental evidence confirming the theoretical prediction of infinite spin diffusion length under specific spin-orbit coupling conditions in GaAs quantum wells.

Findings

Experimental evidence of infinite spin diffusion length

Confirmation of theoretical predictions by Koralek et al.

Reinforcement of the role of Dresselhaus and Rashba couplings

Abstract

In this note, we show that the latest spin grating measurement of spin helix by Koralek {\em et al.} [Nature {\bf 458}, 610 (2009)] provides strong evidence of the infinite spin diffusion length of any spin polarization along the direction perpendicular to the effective magnetic field from the Dresselhaus and Rashba spin-orbit couplings with identical strengths in $(001)$ GaAs quantum wells, predicted by Cheng {\em et al.} [Phys. Rev. B {\bf 75}, 205328 (2007)].