Intrinsic spin Hall effect in platinum metal

TL;DR

This paper demonstrates that the large spin Hall effect in platinum is primarily intrinsic, arising from band structure effects, with detailed calculations showing high spin Hall conductivity and its temperature dependence.

Contribution

It provides first-principles calculations revealing the intrinsic origin of the spin Hall effect in platinum, emphasizing the role of band structure and spin-orbit coupling.

Findings

Intrinsic spin Hall conductivity is ~2000 (ħ/e)(Ω·cm) at low temperature.

SHC decreases to ~200 (ħ/e)(Ω·cm) at room temperature.

Vertex correction due to impurity scattering vanishes, confirming intrinsic nature.

Abstract

Spin Hall effect in metallic Pt is studied with first-principles relativistic band calculations. It is found that intrinsic spin Hall conductivity (SHC) is as large as $\sim 2000 (\hbar/e)(\Omega {\rm cm})^{-1}$ at low temperature, and decreases down to $\sim 200 (\hbar/e)(\Omega {\rm cm})^{-1}$ at room temperature. It is due to the resonant contribution from the spin-orbit splitting of the doubly degenerated $d$-bands at high-symmetry $L$ and $X$ points near the Fermi level. By modeling these near degeneracies by effective Hamiltonian, we show that SHC has a peak near the Fermi energy and that the vertex correction due to impurity scattering vanishes. We therefore argue that the large spin Hall effect observed experimentally in platinum is of intrinsic nature.