Spin-Current-Induced Charge Accumulation and Electric Current in Semiconductor Nanostructures with Rashba Spin-Orbit Coupling

TL;DR

This paper shows how spin currents with different polarizations induce distinct charge accumulation patterns and electric currents in semiconductor nanostructures with Rashba spin-orbit coupling, providing a new way to detect spin currents.

Contribution

It introduces a method to distinguish spin current polarizations by analyzing charge accumulation and electric current patterns in Rashba-coupled nanostructures.

Findings

In-plane polarized spin currents cause charge accumulation at edges or center.

Out-of-plane polarized spin currents generate opposite charge signs at edges, leading to Hall voltage.

The results suggest a new experimental approach to detect pure spin currents.

Abstract

We demonstrate that the flow of a longitudinal spin current with different spin polarization will induce different patterns of charge accumulation in a two-terminal strip, or electric current distribution in a four-terminal Hall-bar structure, of two-dimensional electron gas with Rashba spin-orbit coupling (RSOC). For an in-plane polarized spin current, charges will accumulate either by the two lateral edges or around the center of the strip structure while, for an out-of-plain polarized spin current, charge densities will show opposite signs by the two lateral edges leading to a Hall voltage. Our calculation offers a new route to experimentally detect or differentiate pure spin currents with various spin polarization.