# Spin-pumping through a varying-thickness MgO interlayer in Fe/Pt system

## TL;DR

This study demonstrates that spin currents can tunnel through a thin MgO interlayer in Fe/Pt bilayers, affecting spin-pumping efficiency and voltage generation, with implications for spintronic device design.

## Contribution

It provides experimental evidence of spin current tunneling through MgO layers up to 2 nm thick in Fe/Pt systems, highlighting the role of ultrathin oxides in spin-pumping.

## Key findings

- Spin currents tunnel through MgO up to 2 nm thick.
- Voltage signals are influenced by rectification and shunting effects.
- Thin MgO layers enable spin transport in spintronic devices.

## Abstract

The spin-pumping mechanism is probed through a tunnelling MgO interlayer in Fe/Pt bilayers. We show by ferromagnetic resonance technique and spin-pumping experiments that spin currents can tunnel through the MgO interlayer for thickness up to 2~{nm} and can produce significant voltages in the Pt layer. The electrical detection of spin-pumping furthermore reveals the critical role of rectification and shunting effects on the generated voltages. The non zero spin current transport through a few monolayers of an insulating interlayer might initiate further studies on the role of very thin oxides in spin-pumping experiments.