Electrical control of spin relaxation anisotropy during drift transport in a two-dimensional electron gas

Abstract

Spin relaxation was studied in a two-dimensional electron gas confined in a wide GaAs quantum well. Recently, the control of the spin relaxation anisotropy by diffusive motion was first shown in D. Iizasa et al., arXiv:2006.08253 (2020). Here, we demonstrate electrical control by drift transport in a system with two-subbands occupied. The combined effect of in-plane and gate voltages was investigated using time-resolved Kerr rotation. The measured relaxation time present strong anisotropy with respect to the transport direction. For an in-plane accelerating electric field along $\left[110\right]$, the lifetime was strongly suppressed irrespective of the applied gate voltage. Remarkably, for transport along $\left[1\bar{1}0\right]$, the data shows spin lifetime that was gate-dependent and longer than in the $\left[110\right]$ direction regardless of the in-plane voltage. In agreement, independent results of anisotropic spin precession frequencies are also presented. Nevertheless, the long spin lifetime, strong anisotropy and drift response seen in the data are beyond the existing models for spin drift and diffusion.

References in corpus (12)

• An Exact SU(2) Symmetry and Persistent Spin Helix in a Spin-Orbit Coupled System
• Emergence of the persistent spin helix in semiconductor quantum wells
• Direct mapping of the formation of a persistent spin helix: Supplementary information
• Intersubband-induced spin-orbit interaction in quantum wells
• Spin-orbit interaction in GaAs wells: From one to two subbands
• Detection of large magneto-anisotropy of electron spin dephasing in a high-mobility two-dimensional electron system in a $[001]$ GaAs/AlGaAs quantum well
• Datta-Das type spin-field effect transistor in non-ballistic regime
• Spin drift and diffusion in one- and two-subband helical systems
• Spin-orbit interaction and spin relaxation in a two-dimensional electron gas
• Characterization of spin-orbit fields in InGaAs quantum wells
• g-Factor Modification in a Bulk InGaAs Epilayer by an In-plane Electric Field
• Experimental analysis of the spin-orbit coupling dependence on the drift velocity of a spin packet

Cited by in corpus (2)

• Spin drift-diffusion for two-subband quantum wells
• Charge-Spin Conversion in Two-Subband Quantum Wells with Conventional and Unconventional Rashba Spin-Orbit Coupling