Controlled formation of high-mobility shallow electron gases in SrTiO3 single crystal

TL;DR

This paper demonstrates a method to create high-mobility, nanoscale electron channels in SrTiO3 using oxygen vacancy doping via Ar+ ion irradiation, enabling advanced oxide electronic applications.

Contribution

It introduces a controlled ion-irradiation technique to form high-mobility electron channels in SrTiO3 with potential for oxide electronics.

Findings

High electron mobility (~15,000 cm^2V^{-1}s^{-1}) achieved in channels

Observation of magnetic quantum oscillations

Gate-tunable linear magnetoresistance

Abstract

We report controlled formation of sub-100 nm-thin electron channels in SrTiO$_3$ by doping with oxygen vacancies induced by Ar$^+$-ion irradiation. The conducting channels exhibit a consistent high electron mobility (~15,000 cm$^2$V$^{-1}$s$^{-1}$), which enables clear observation of magnetic quantum oscillations, and gate-tunable linear magnetoresistance. Near the onset of electrical conduction, the metal-insulator transition is induced by the mobility suppression. With the high electron mobility and the ease of controlled channel formation, this ion-irradiation doping method may provide an excellent basis for developing oxide electronics.