Li intercalation effects on magnetism in undoped and Co-doped anatase TiO$_2$

TL;DR

This study investigates how lithium intercalation affects the magnetic properties of undoped and cobalt-doped anatase TiO₂, revealing carrier localization and magnetic moment suppression due to intercalation.

Contribution

It demonstrates the localized nature of n-type carriers at Ti sites and shows how Li intercalation suppresses magnetism in Co-doped TiO₂, providing insights into magnetic control via doping.

Findings

Li intercalation localizes carriers at Ti sites near Li

Local spins form at Ti with increased intercalation

Li intercalation suppresses Co magnetic moments

Abstract

The effects of $n$-type carrier doping by Li intercalation on magnetism in undoped and Co-doped anatase TiO$_2$ are investigated. We have found that doped $n$-type carriers in TiO$_2$ are localized mainly at Ti sites near the intercalated Li. With increasing the intercalation, local spins are realized at Ti. In the case of Co-doped TiO$_2$, most of the added $n$-type carriers fill the Co 3$d$ bands and the rest are localized at Ti. Therefore, Co magnetic moment vanishes by Li intercalation to have a nonmagnetic ground state.