Enhancement of Spin Currents in a Lattice near the Curie Point

TL;DR

This paper demonstrates that spin currents in a paramagnetic lattice can be significantly enhanced near the Curie point due to exchange interactions and paramagnon flow, offering insights into magnetic spin transport.

Contribution

It introduces a mechanism for enhancing pure spin currents near the Curie temperature through exchange interactions and paramagnon dynamics.

Findings

Spin currents are enhanced near the Curie point.

Exchange interactions partially align magnetic moments.

Paramagnon flow contributes to increased spin current.

Abstract

We show that pure spin currents carried by conduction electrons injected into a paramagnetic lattice of mutually interacting localized magnetic moments can be enhanced close to the Curie temperature by the exchange interaction between the lattice sites and the non vanishing spin density associated with the spin current. The latter partially aligns the magnetic moments of the lattice, generating a flow of paramagnons that contribute to the total spin current.