# Optical probing of the intrinsic spin Hall effect in a high mobility GaAs p-doped quantum well

## TL;DR

This study demonstrates the detection of the intrinsic spin Hall effect in a high mobility GaAs quantum well through spatially resolved optical measurements, revealing edge spin polarization induced by an electric field.

## Contribution

It introduces a novel optical probing method to detect the intrinsic spin Hall effect in a high mobility GaAs heterostructure using spatially resolved spectroscopy.

## Key findings

- Edge spin polarization of up to 11% measured
- Linear dependence of spin polarization on electric field observed
- Spatially resolved spectroscopy effectively probes edge states

## Abstract

We report on the detection of the intrinsic spin Hall effect in a modulation doped Al-GaAs/GaAs/AlGaAs heterostructure bounded by a self-aligned pn-junction, fabricated by the cleaved edge overgrowth method. Light emission due to the recombination of electrons and spin-polarized holes was generated and mapped with a spatial resolution of one micrometer. An edge accumulated spin polarization of up to 11% was measured, induced solely by application of an electric Field perpendicular to the pn-junction. Using a quantum dot structure as light source, a linear dependence of the effective spin polarization, and with that the dominance of the spin Hall effect, with the electric field is seen. Spatially resolved spectroscopy from an epitaxially fabricated LED is demonstrated to be a valuable tool to probe the edge states of electron and hole gases in reduced dimensions.