Spin-filtering effect in the transport through a single-molecule magnet Mn$_{12}$ bridged between metallic electrodes

TL;DR

This study demonstrates that a single-molecule magnet Mn$_{12}$ can act as a spin filter in electronic transport, with majority spin orbitals dominating conductance near the Fermi level, promising for spintronic applications.

Contribution

It provides a theoretical demonstration of spin-filtering in Mn$_{12}$ molecules bridged between electrodes using advanced quantum transport calculations.

Findings

Resonant tunneling occurs through majority spin orbitals near the Fermi level.

A spin-filtering effect persists at low bias voltages.

The effect remains robust even when electron correlations are included.

Abstract

Electronic transport through a single-molecule magnet Mn$_{12}$ in a two-terminal set up is calculated using the non-equilibrium Green's function method in conjunction with density-functional theory. A single-molecule magnet Mn$_{12}$ is bridged between Au(111) electrodes via thiol group and alkane chains such that its magnetic easy axis is normal to the transport direction. A computed spin-polarized transmission coefficient in zero-bias reveals that resonant tunneling near the Fermi level occurs through some molecular orbitals of majority spin only. Thus, for low bias voltages, a spin-filtering effect such as only one spin component contributing to the conductance, is expected. This effect would persist even with inclusion of additional electron correlations.