Strain tuning of oxygen vacancy channels in SrCoO2.5 thin films

Tuning of the oxygen vacancy channels (OVCs) ordering is crucial to control ionic conduction, which has much promise in energy materials and memory devices. Brownmillerite (BM) oxides have been proven to be an ideal playground for exploring the modulation of OVCs through external stimuli. In the BM-SrCoO2.5 thin films, we observed that in-plane compressive strain promotes horizontal OVCs, while in-plane tensile strain facilitates vertical OVCs. The modulation of the OVCs can also be made through electric biasing utilizing the piezo-strain. The selective regulation of the orientation of the OVCs in BM-SrCoO2.5 thin films through strain engineering will significantly enhance the development and implementation of functional features for ion transport and migration-related functionality.