Fast optical control of spin dynamics in a quantum wire

TL;DR

This paper demonstrates rapid optical control of spin dynamics in a quantum wire with Rashba spin-orbit interaction, enabling tunable spin precession and phase coherence for spintronic applications.

Contribution

It introduces a method for controlling spin dynamics in quantum wires using shaped sub-picosecond electromagnetic pulses, a novel approach for spintronics.

Findings

Optical pulses can control spin precession in quantum wires.

Spin coherence is maintained during optical control.

The spin dynamics are tunable via pulse polarization and parameters.

Abstract

The spin dynamics in a quantum wire with a Rashba spin orbit interaction (SOI) is shown to be controllable via sub-picosecond electromagnetic pulses shaped appropriately. If the light polarization vector is along the wire's direction, the carriers experience a momentum boost while the phase coherence in different spin channels is maintained, a fact exploitable to control the speed of a photo-driven spin field effect transistor. A photon pulse with a polarization vector perpendicular to the wire results in a spin precession which is comparable to that due to the Rashba SOI and is tunable by the pulse field parameters, an effect utilizable in optically controlled spintronics devices.