Paramagnetic spin pumping

TL;DR

This study demonstrates spin pumping from a paramagnetic insulator La2NiMnO6 into a Pt film, showing inverse spin Hall voltage detection above the ferromagnetic transition temperature, driven by ferromagnetic correlations.

Contribution

It reveals that efficient spin pumping can occur in the paramagnetic phase due to ferromagnetic correlations, expanding understanding beyond ferromagnetic order.

Findings

Spin pumping observed in La2NiMnO6 above TC

Inverse spin Hall voltage detected in Pt layer

Ferromagnetic correlations enable spin pumping in paramagnetic state

Abstract

We have demonstrated spin pumping from a paramagnetic state of an insulator La2NiMnO6 into a Pt film. Single-crystalline films of La2NiMnO6 which exhibit a ferromagnetic order at TC ~ 270 K were grown by pulsed laser deposition. The inverse spin Hall voltage induced by spin-current injection has been observed in the Pt layer not only in the ferromagnetic phase of La2NiMnO6 but also in a wide temperature range above TC. The efficient spin pumping in the paramagnetic phase is ascribable to ferromagnetic correlation, not to ferromagnetic order.