Conditions for the generation of spin currents in spin-Hall devices

TL;DR

This paper explores the conditions under which spin currents can be generated in spin-Hall devices, revealing that device geometry and charge accumulation critically influence the generation of transverse spin and charge currents.

Contribution

It demonstrates how the least dissipation principle explains the absence or presence of spin currents in different device geometries, providing new insights into spin-Hall device behavior.

Findings

Hall bar geometry prevents transverse spin currents due to minimum dissipation

Corbino disk geometry allows transverse spin currents

Charge accumulation inhibits spin to charge current conversion

Abstract

We investigate the out-of-equilibrium stationary states of spin-Hall devices on the basis of the least dissipation principle. We show that, for a bulk paramagnet with spin-orbit interaction, in the case of the Hall bar geometry the principle of minimum dissipated power prevents the generation of transverse spin and charge currents while in the case of the Corbino disk geometry, transverse currents can be produced. More generally, we show that electric charge accumulation prevents the stationary spin to charge current conversion.