Platinum thickness dependence of the inverse spin-Hall voltage from spin pumping in a hybrid YIG/Pt system

TL;DR

This study experimentally investigates how the platinum layer thickness affects the inverse spin-Hall voltage generated by spin pumping in a YIG/Pt system across various frequencies and power levels, revealing unexpected behavior.

Contribution

First experimental demonstration of platinum thickness dependence of inverse spin-Hall voltage in a YIG/Pt system over a broad frequency range.

Findings

Observed strong enhancement of $eltaV/R$ ratio with Pt thickness

Behavior not explained by existing spin transport models

Results differ from previous NiFe/Pt studies

Abstract

We show the first experimental observation of the platinum (Pt) thickness dependence in a hybrid YIG/Pt system of the inverse spin-Hall effect from spin pumping, over a large frequency range and for different rf powers. From the measurement of the dc voltage ($\Delta\textrm{V}$) at the resonant condition and the resistance ($R$) of the Pt layer, a strong enhancement of the ratio $\Delta\textrm{V}/R$ has been observed, which is not in agreement with previous studies on the NiFe/Pt system. The origin of this behaviour is still unclear and cannot be explained by the spin transport model that we have used.