Electric field-driven coherent spin reorientation of optically generated electron spin packets in InGaAs

TL;DR

This paper demonstrates electric field pulses can coherently control and reorient electron spins in InGaAs, enabling arbitrary spin rotations and revealing partial spin rephasing effects.

Contribution

It introduces a method for phase-coherent spin rotation using electric field pulses acting as local magnetic field pulses in InGaAs.

Findings

Electric field pulses achieve +/- pi spin rotations.

Electric field control enables arbitrary spin orientations.

Partial spin rephasing doubles the spin dephasing time.

Abstract

Full electric-field control of spin orientations is one of the key tasks in semiconductor spintronics. We demonstrate that electric field pulses can be utilized for phase-coherent +/- pi spin rotation of optically generated electron spin packets in InGaAs epilayers detected by time-resolved Faraday rotation. Through spin-orbit interaction, the electric-field pulses act as local magnetic field pulses (LMFP). By the temporal control of the LMFP, we can turn on and off electron spin precession and thereby rotate the spin direction into arbitrary orientations in a 2-dimensional plane. Furthermore, we demonstrate a spin echo-type spin drift experiment and find an unexpected partial spin rephasing, which is evident by a doubling of the spin dephasing time.