Temperature Dependence of Spin Hall Angle of Palladium

TL;DR

This paper experimentally investigates how the spin Hall angle of palladium varies with temperature, revealing an increase to approximately 0.02 at 123 K using spin pumping techniques.

Contribution

It provides the first detailed measurement of palladium's spin Hall angle dependence on temperature through spin pumping experiments.

Findings

Spin Hall angle increases with decreasing temperature.

Maximum value of about 0.02 at 123 K.

Temperature significantly affects spin-charge conversion efficiency.

Abstract

In this study, the temperature dependence of the spin Hall angle of palladium (Pd) was experimentally investigated by spin pumping. A Ni80Fe20/Pd bilayer thin film was prepared, and a pure spin current was dynamically injected into the Pd layer. This caused the conversion of the spin current to a charge current owing to the inverse spin Hall effect. It was found that the spin Hall angle varies as a function of temperature, whereby the value of the spin Hall angle increases to ca. 0.02 at 123 K.