A Microscopic Explanation of Microwave Spin Pumping

TL;DR

This paper reveals that Microwave Spin Pumping was first predicted and observed in the 1950s through Magnetic Resonance techniques, establishing a foundational link between historical magnetic resonance and modern spintronics.

Contribution

It uncovers the historical origins of Microwave Spin Pumping and connects it to Magnetic Resonance, offering a new perspective that unifies past and present spintronics research.

Findings

Microwave Spin Pumping was predicted and observed in the 1950s.

The discovery was linked to Dynamic Nuclear Polarisation.

This connection unifies magnetic resonance and spintronics concepts.

Abstract

We contend that Microwave Spin Pumping was first predicted and observed - albeit using a different and more sensitive detection mechanism than Inverse Spin Hall Effect - in the 1950's. This discovery was the founding step in the widely used analytical tool that is now known as Dynamic Nuclear Polarisation. Recognising this hitherto unsung connection between 20th Century Magnetic Resonance and 21st Century Spintronics not only helps to explain and unify contemporary metallic spin pumping observations: it is also the key to unlocking the immense and very sophisticated toolbox of Magnetic Resonance and placing it at the disposal of the future of Spintronics.