Suppressed spin dephasing for 2D and bulk electrons in GaAs wires due to engineered cancellation of spin-orbit interaction terms

TL;DR

This study demonstrates that engineering the Rashba and Dresselhaus spin-orbit interactions in GaAs wires can significantly suppress spin dephasing, especially along the [110] direction, applicable to both quantum well and bulk electrons.

Contribution

It reveals a method to suppress spin dephasing by canceling spin-orbit terms, effective in both quantum well and bulk electron systems.

Findings

Suppressed spin dephasing observed in GaAs wires along [110] direction.

Spin-orbit cancellation mechanism effective in quantum well and bulk electrons.

Anisotropic spin-orbit fields enhance suppression of dephasing.

Abstract

We report a study of suppressed spin dephasing for quasi-one-dimensional electron ensembles in wires etched into a GaAs/AlGaAs heterojunction system. Time-resolved Kerr-rotation measurements show a suppression that is most pronounced for wires along the [110] crystal direction. This is the fingerprint of a suppression that is enhanced due to a strong anisotropy in spin-orbit fields that can occur when the Rashba and Dresselhaus contributions are engineered to cancel each other. A surprising observation is that this mechanisms for suppressing spin dephasing is not only effective for electrons in the heterojunction quantum well, but also for electrons in a deeper bulk layer.