Coherent Propagation of Spin Helices in a Quantum-Well Confined Electron Gas

Abstract

We use phase-resolved transient grating spectroscopy to measure the propagation of spin helices in a high mobility $n$-GaAs/AlGaAs quantum well with an applied in-plane electric field. At relatively low fields helical modes crossover from overdamped excitations where the spin-precession period exceeds the spin lifetime, to a regime of coherent propagation where several spin-precession periods can be observed. We demonstrate that the envelope of a spin polarization packet reaches a current-driven velocity of 10${}^7$ cm s${}^{-1}$ in an applied field of 70 V cm${}^{-1}$.

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Cited by in corpus (1)

• Evolution of the persistent spin helix in the presence of Hartree-Fock fields