Controlling high-mobility conduction in SrTiO3 by oxide thin film deposition

SrTiO3 becomes a high-mobility metallic conductor when doped with oxygen vacancies at low concentrations (>= 10(16) cm(-3)). We show that the vacancy concentration in the SrTiO3 single crystal substrates could be controllably tuned by changing the thickness of oxide films (deposited by pulsed laser deposition at high temperature and low oxygen pressure). The obtained variation in the carrier density strongly influences the transport properties. The quantitative analysis of the experimental results leads toward new and accurate strategies for the design of multifunctional oxide heterostructures for electronics and spintronics.