Proximity Effect of Epitaxial Iron Phthalocyanine Molecules on High-Quality Graphene Devices

TL;DR

This study explores how epitaxial iron phthalocyanine molecules induce magnetic effects in high-quality graphene, revealing potential for molecular spintronic applications despite some mobility degradation.

Contribution

It demonstrates the magnetic proximity effect of FePc molecules on graphene, showing induced magnetic states and spin-Hall effects in a novel heterostructure.

Findings

Magnetic proximity induces canted antiferromagnetic state in monolayer graphene.

Pronounced Zeeman spin-Hall effect observed in bilayer graphene with FePc.

Long-range scattering dominates in bilayer graphene/FePc heterostructures.

Abstract

Depositing magnetic insulators on graphene has been a promising route to introduce magnetism via exchange proximity interaction in graphene for future spintronics applications. Molecule-based magnets may offer unique opportunities because of their synthesis versatility. Here, we investigated the magnetic proximity effect of epitaxial iron phthalocyanine (FePc) molecules on high-quality monolayer and bilayer graphene devices on hexagonal boron nitride substrate by probing the local and non-local transport. Although the FePc molecules introduce large hole doping effects combined with mobility degradation, the magnetic proximity gives rise to a canted antiferromagnetic state under a magnetic field in the monolayer graphene. On bilayer graphene and FePc heterostructure devices, the non-local transport reveals a pronounced Zeeman spin-Hall effect. Further analysis of the scattering mechanism in the bilayer shows a dominated long-range scattering. Our findings in graphene/organic magnetic insulator heterostructure provide a new insight for the use of molecule-based magnets in two-dimensional spintronic devices.