Transverse electric current induced by optically injected spin current in cross-shaped InGaAs/InAlAs system

TL;DR

This paper demonstrates that optically injected spin currents in a cross-shaped InGaAs/InAlAs system induce measurable transverse charge currents, providing a potential method for detecting spin currents via electrical signals.

Contribution

The study introduces a theoretical framework showing how spin currents generated by polarized light can produce detectable transverse charge currents in a specific semiconductor structure.

Findings

Spin current induces transverse charge currents.

Transverse currents are observable experimentally.

Provides a method to probe spin currents electrically.

Abstract

We examine electric response of a linearly polarized light normally shed on a cross-shaped quasi 2-dimensional InGaAs/InAlAs system with structure inversion asymmetry. The photo-excited conduction electrons carry a pure spin current with in-plane spin polarization due to the Rashba spin-orbit interaction. We use Landauer-B\"{u}ttiker formalism to show that this spin current induces two inward or outward transverse charge currents, which are observable in experiments. This effect may serve as an experimental probe of certain types of spin current.