Experimental observation of spin to charge current conversion at non-magnetic metal/Bi2O3 interfaces

TL;DR

This study demonstrates interfacial spin to charge current conversion at Cu/Bi2O3 interfaces via spin pumping from Permalloy, with conversion efficiency depending on Cu thickness, revealing insights into spin-charge interconversion mechanisms.

Contribution

First experimental observation of spin to charge current conversion at non-magnetic metal/Bi2O3 interfaces using spin pumping from Permalloy.

Findings

Clear spin to charge conversion observed in Py/Cu/Bi2O3 trilayer.

No conversion signature in bilayer films without Bi2O3.

Conversion coefficient varies with Cu thickness, indicating momentum relaxation effects.

Abstract

We here demonstrate the interfacial spin to charge current conversion by means of spin pumping from a ferromagnetic Permalloy (Py: Ni80Fe20) to a Cu/Bi2O3 interface. A clear signature of the spin to charge current conversion was observed in voltage spectrum of a Py/Cu/Bi2O3 trilayer film whereas no signature in a Py/Cu and Py/Bi2O3 bilayer films. We also found that the conversion coefficient strongly depended on Cu thickness, reflecting the thickness dependent momentum relaxation time in Cu layer.