Observation of huge thermal spin currents in magnetic multilayers

TL;DR

This paper reports a significant enhancement of thermal spin currents in multilayer ferromagnet/metal structures, demonstrating a giant spin Seebeck effect due to magnon-electron interconversion at interfaces, advancing spintronics applications.

Contribution

It introduces a novel multilayer structure that produces large thermal spin currents, overcoming previous limitations of weak intensity in thermal spin pumping.

Findings

Giant spin Seebeck effect observed in multilayer structures

Enhanced spin current due to multiple interface interconversions

Potential for improved thermal spin current applications in spintronics

Abstract

Thermal spin pumping constitutes a novel mechanism for generation of spin currents; however their weak intensity constitutes a major roadblock for its usefulness. We report a phenomenon that produces a huge spin current in the central region of a multilayer system, resulting in a giant spin Seebeck effect in a structure formed by repetition of ferromagnet/metal bilayers. The result is a consequence of the interconversion of magnon and electron spin currents at the multiple interfaces. This work opens the possibility to design thin film heterostructures that may boost the application of thermal spin currents in spintronics.