Calculating interface transport parameters at finite temperatures: Nonmagnetic interfaces

TL;DR

This paper uses first-principles calculations to determine key spin transport parameters at nonmagnetic metal interfaces at room temperature, revealing their significant impact on spintronic experiments.

Contribution

It introduces a method to extract interface resistance, spin memory loss, and spin Hall angle at finite temperatures using first-principles scattering calculations.

Findings

Significant interface resistance, spin memory loss, and spin Hall angle values were found.

Temperature dependence of interface parameters was characterized for Au|Pt.

Results have important implications for nonmagnetic spintronic devices.

Abstract

First-principles scattering calculations are used to investigate spin transport through interfaces between diffusive nonmagnetic metals where the symmetry lowering leads to an enhancement of the effect of spin-orbit coupling (SOC) and to a discontinuity of the spin currents passing through the interfaces. From the conductance and local spin currents calculated for nonmagnetic bilayers, we extract values of the room temperature interface resistance $R_{\rm I}$, of the spin memory loss parameter $\delta$ and of the interface spin Hall angle $\Theta_{\rm I}$ for nonmagnetic Au$|$Pt and Au$|$Pd interfaces using a frozen thermal disorder scheme to model finite temperatures. Substantial values of all three parameters are found with important consequences for experiments involving nonmagnetic spacer and capping layers. The temperature dependence of the interface parameters is determined for Au$|$Pt.