Role of charge carriers for ferromagnetism in cobalt-doped rutile TiO2

TL;DR

This study investigates how charge carriers influence high-temperature ferromagnetism in cobalt-doped rutile TiO2 thin films, revealing that increased electron density and cobalt content induce ferromagnetic behavior.

Contribution

It demonstrates experimentally that charge carriers are key to ferromagnetism in cobalt-doped TiO2, providing insights into the material's magnetic mechanisms.

Findings

High electron densities correlate with ferromagnetism.

Cobalt content affects magnetic properties.

Charge carriers induce ferromagnetism in TiO2.

Abstract

Electric and magnetic properties of a high temperature ferromagnetic oxide semiconductor, cobalt-doped rutile TiO2, are summarized. The cobalt-doped rutile TiO2 epitaxial thin films with different electron densities and cobalt contents were grown on r-sapphire substrates with laser molecular beam epitaxy. Results of magnetization, magnetic circular dichroism, and anomalous Hall effect measurements were examined for samples with systematically varied electron densities and cobalt contents. The samples with high electron densities and cobalt contents show the high temperature ferromagnetism, suggesting that charge carriers induce the ferromagnetism.