Controlling the magnetism of oxygen surface vacancies in strontium titanate $\mathrm{(SrTiO_3\!)}$ through charging

TL;DR

This study demonstrates how the magnetism of oxygen vacancies on SrTiO3 surfaces can be precisely controlled through charge doping, offering a potential method for tunable magnetic properties in oxide materials.

Contribution

It introduces a first-principles approach to controllably tune oxygen vacancy magnetism in SrTiO3 via chemical potential adjustments, considering various external influences.

Findings

Magnetism of oxygen vacancies can be quenched or stabilized by doping.

Control of vacancy magnetization is robust against external factors.

Potential experimental methods for magnetic control are discussed.

Abstract

We discuss, based on first principles calculations, the possibility to tune the magnetism of oxygen vacancies at the (001) surface of strontium titanate $(\mathrm{SrTiO_3}\!)$. The magnetic moment of single and clustered vacancies stemming from Ti-O broken bonds can be both quenched and stabilized controllably by chemical potential adjustment associated with doping the system with electrons or holes. We discuss to what extent this route to magnetization state control is robust against other external influences like chemical doping, mechanical action and electric field. Such control of vacancy state and magnetization can conceivably be achieved experimentally by using local probe tips.