Oxygen vacancies in proximity to surfaces and heterointerfaces in oxide thin film heterostructures have major effects on properties, resulting, for example, in emergent conduction behaviour, large changes in metal-insulator transition temperatures or enhanced catalytic activity. Here we report the discovery of a means of reversibly controlling the oxygen vacancy concentration and distribution in oxide heterostructures consisting of electronically conducting In₂O₃ films grown on ionically conducting Y₂O₃-stabilized ZrO₂ substrates. Oxygen ion redistribution across the heterointerface is induced using an applied electric field oriented in the plane of the interface, resulting in controlled oxygen vacancy (and hence electron) doping of the film and possible orders-of-magnitude enhancement of the film's electrical conduction. The reversible modified behaviour is dependent on interface properties and is attained without cation doping or changes in the gas environment.

Nature Communications 7, Article number: 11892 doi:10.1038/ncomms11892
Received 05 August 2015 Accepted 10 May 2016 Published 10 June 2016

http://www.nature.com/ncomms/2016/160610/ncomms11892/full/ncomms11892.html