Spin-splitting in GaAs 2D holes

Abstract

We present quantitative measurements and calculations of the spin-orbit induced zero-magnetic-field spin-splitting in two-dimensional (2D) hole systems in modulation-doped GaAs (311)A quantum wells. The results show that the splitting is large and tunable. In particular, via a combination of back- and front-gate biases, we can tune the splitting while keeping the 2D hole density constant. The data also reveal a surprising result regarding the magnetoresistance (Shubnikov-de Haas) oscillations in a 2D system with spin-split energy bands: the frequencies of the oscillations are {\it not} simply related to the population of the spin-subbands. Next we concentrate on the metallic-like behavior observed in these 2D holes and its relation to spin-splitting. The data indicate that the metallic behavior is more pronounced when two spin-subbands with unequal populations are occupied. Our measurements of the magnetoresistance of these 2D hole systems with an in-plane magnetic field corroborate this conclusion: while the system is metallic at zero magnetic field, it turns insulating when one of the spin-subbands is depopulated at high magnetic field.

To be published in Physica E, as part of the proceedings of the 11th International Winterschool on New Developments in Solid State Physics held in Mauterndorf, Austria, February, 2000

References in corpus (7)

• Spin Degree of Freedom in a Two-Dimensional Electron Liquid
• The Effect of Spin Splitting on the Metallic Behavior of a Two-Dimensional System
• Parallel Magnetic Field Induced Transition in Transport in the Dilute Two-Dimensional Hole System in GaAs
• Parallel magnetic field induced giant magnetoresistance in low density {\it quasi}-two dimensional layers
• Apparent Metallic Behavior at B = 0 of a two-dimensional electron system in AlAs
• Anomalous magneto-oscillations in two-dimensional systems
• On the Relation between Interband Scattering and the "Metallic Phase" of Two Dimensional Holes in GaAs/AlGaAs

Cited by in corpus (11)

• Gate-Controlled Spin-Orbit Quantum Interference Effects in Lateral Transport
• Spin polarization of electrons by non-magnetic heterostructures : basics of spin-optics
• Spin-Hall transport of heavy holes in III-V semiconductor quantum wells
• Hole spin dephasing in $p$-type semiconductor quantum wells
• Negative differential Rashba effect in two-dimensional hole systems
• Spin Splitting in GaAs (100) Two-Dimensional Holes
• Tuning of the spin-orbit interaction in two-dimensional GaAs holes via strain
• Strain-induced Fermi contour anisotropy of GaAs 2D holes
• Non-Markovian hole spin kinetics in $p$-type GaAs quantum wells
• Tuning of Fermi Contour Anisotropy in GaAs (001) 2D Holes via Strain
• Anisotropic low-temperature piezoresistance in (311)A GaAs two-dimensional holes