Atomically Resolved Spin-Dependent Tunnelling on the Oxygen-Terminated Fe3O4 (111)

TL;DR

This study uses spin-polarized STM to investigate atomic-scale spin-dependent tunneling on oxygen-terminated Fe3O4 (111), revealing how surface defects influence local spin transport properties at room temperature.

Contribution

It provides the first atomic-scale analysis of spin-dependent tunneling on Fe3O4 (111) and shows the impact of surface vacancies on TMR.

Findings

Significant magnetic contrast observed at atomic scale.

Tunneling magnetoresistance variations up to 250%.

Surface defects strongly affect local spin transport.

Abstract

We employ spin-polarized (SP) STM to study the spin-dependent tunneling between a magnetite (111) sample and an antiferromagnetic tip through a vacuum barrier at room temperature. Atomic scale STM images show significant magnetic contrast corresponding to variations in the local surface states induced by oxygen vacancies. The estimated variations in tunneling magnetoresistance (TMR) of 250% suggest that the spin-transport properties are significantly altered locally by the presence of surface defects.