Molecular Anisotropic Magnetoresistance

TL;DR

This paper demonstrates that molecular junctions with ferromagnetic leads can exhibit greatly enhanced anisotropic magnetoresistance due to spin-orbit coupling and orbital filtering, offering tunable magnetic transport properties.

Contribution

It reveals that molecular junctions can significantly amplify AMR effects through spin-orbit coupling and orbital symmetry filtering, a novel approach in spintronics.

Findings

Gigantic AMR observed in metal-benzene molecular junctions.

Spin-orbit coupling and orbital filtering are key to enhanced AMR.

Tunable magnetoresistance achieved by material choice.

Abstract

Using density functional theory calculations, we demonstrate that the effect of anisotropic magnetoresistance (AMR) can be enhanced by orders of magnitude with respect to conventional bulk ferromagnets in junctions containing molecules sandwiched between ferromagnetic leads. We study ballistic transport in metal-benzene complexes contacted by $3d$ transition-metal wires. We show that the gigantic AMR can arise from spin-orbit coupling effects in the leads, drastically enhanced by orbital-symmetry filtering properties of the molecules. We further discuss how this molecular anisotropic magnetoresistance (MAMR) can be tuned by proper choice of materials and their electronic properties.