Spintronics Detection of Interfacial Magnetic Switching in a Paramagnetic Tris(8-hydroxyquinoline)iron(III) Thin Film

TL;DR

This paper demonstrates magnetic switching in a paramagnetic organic thin film using spintronic techniques, bridging organic and molecular spintronics through electrical and microwave measurements.

Contribution

It provides experimental evidence of interfacial magnetic switching in a paramagnetic molecule via spintronic methods, a novel approach in organic spintronics.

Findings

Magnetic switching observed in Feq3 thin film on ferromagnetic substrate.

Spin transport effects confirmed by magnetoresistance and inverse spin Hall effect.

Potential for macroscopic organic spintronic devices from molecular-level control.

Abstract

Organic semiconductors find increasing importance in spin transport devices due to the modulation and control of their properties through chemical synthetic versatility. The organic materials are used as interlayers between two ferromagnet (FM) electrodes in organic spin valves (OSV), as well as for magnetic spin manipulation of metal-organic complexes at the molecular level. In the latter, specifically, the substrate-induced magnetic switching in a paramagnetic molecule has been evoked extensively, but studied by delicate surface spectroscopies. Here we present evidence of the substantial magnetic switching in a nanosized thin film of the paramagnetic molecule, tris(8-hydroxyquinoline)iron(III) (Feq3) deposited on a FM substrate, using the magnetoresistance response of electrical spin-injection in an OSV structure, and the inverse-spin-Hall effect induced by state-of-art pulsed microwave spin-pumping. We show that interfacial spin control at the molecular level may lead to a macroscopic organic spin transport device, thus, bridging the gap between organic spintronics and molecular spintronics.