Spin-Relaxation Mechanisms in InAs Quantum Well Heterostructures

TL;DR

This study investigates spin-relaxation mechanisms in InAs quantum wells using magnetoconductance measurements, revealing distinct regimes and spin-scattering processes relevant for spintronic device applications.

Contribution

It identifies and characterizes two transport regimes and spin-scattering mechanisms in InAs quantum wells through experimental data and theoretical modeling.

Findings

Two distinct transport regimes corresponding to quantum well sub-bands.

Different spin-scattering mechanisms in each sub-band regime.

Spin-orbit splitting energy varies between regimes.

Abstract

The spin-orbit interaction and spin-relaxation mechanisms of a shallow InAs quantum well heterostructure are investigated by magnetoconductance measurements as a function of an applied top-gate voltage. The data were fit using the Iordanskii--Lyanda-Geller--Pikus model and two distinct transport regimes were identified which correspond to the first and second sub-bands of the quantum well. The spin-orbit interaction splitting energy is extracted from the fits to the data, which also displays two distinct regimes. The different sub-band regimes exhibit different spin-scattering mechanisms, the identification of which, is of relevance for device platforms of reduced dimensionality which utilise the spin-orbit interaction.