Optimization of the yttrium iron garnet/platinum interface for spin pumping-based applications

TL;DR

This study investigates how surface processing of yttrium iron garnet (YIG) affects spin pumping efficiency and spin mixing conductance when interfaced with platinum, demonstrating significant improvements through optimized preparation.

Contribution

It provides a quantitative analysis of the impact of surface treatment on YIG/Pt interfaces, revealing over two orders of magnitude enhancement in spin pumping performance.

Findings

Enhanced inverse spin Hall voltage with better surface processing.

Significant increase in spin mixing conductance due to interface optimization.

Strong dependence of spin pumping efficiency on YIG surface condition.

Abstract

The dependence of the spin pumping efficiency and the spin mixing conductance on the surface processing of yttrium iron garnet (YIG) before the platinum (Pt) deposition has been investigated quantitatively. The ferromagnetic resonance driven spin pumping injects a spin polarized current into the Pt layer, which is transformed into an electromotive force by the inverse spin Hall effect. Our experiments show that the spin pumping effect indeed strongly depends on the YIG/Pt interface condition. We measure an enhancement of the inverse spin Hall voltage and the spin mixing conductance of more than two orders of magnitude with improved sample preparation.