Spin-flip diffusion length in 5d transition metal elements: a first-principles benchmark

TL;DR

This study provides first-principles calculations of the spin-flip diffusion length in all 5d transition metals, revealing its inverse relation to the density of states at the Fermi level and its temperature dependence.

Contribution

It offers a comprehensive first-principles benchmark of spin-flip diffusion lengths in 5d metals, linking them to electronic structure and temperature effects.

Findings

$l_{sf}$ inversely proportional to density of states at Fermi level

Products $ ho(T)l_{sf}(T)$ and $ heta_{sH}(T)l_{sf}(T)$ are temperature-independent

$l_{sf}$ does not decrease monotonically with atomic number Z

Abstract

Little is known about the spin-flip diffusion length $l_{\rm sf}$, one of the most important material parameters in the field of spintronics. We use a density-functional-theory based scattering approach to determine values of $l_{\rm sf}$ that result from electron-phonon scattering as a function of temperature for all 5d transition metal elements. $l_{\rm sf}$ does not decrease monotonically with the atomic number Z but is found to be inversely proportional to the density of states at the Fermi level. By using the same local current methodology to calculate the spin Hall angle $\Theta_{\rm sH}$ that characterizes the efficiency of the spin Hall effect, we show that the products $\rho(T)l_{\rm sf}(T)$ and $\Theta_{\rm sH}(T)l_{\rm sf}(T)$ are constant.