Enhancing interfacial conductivity and spatial charge confinement of LaAlO3/SrTiO3 heterostructures via strain engineering

We explored the possibility of enhancing interfacial conductivity and spatial charge confinement of LaAlO3/SrTiO3 (LAO/STO) heterostructure (HS) via strain engineering using first-principles electronic structure calculations. We found that applying a tensile strain on the STO substrate along the ab-plane can significantly enhance the interfacial conductivity, magnetic moments, and the spatial charge confinement of the HS system. In contrast, a compressive strain can dilute the interfacial charge carrier density, make the mobile charges transfer to deep STO substrate, and weaken the spatial charge confinement along the c-axis. Hence, we propose that applying a tensile strain can be an effective way to enhance the interfacial conductivity and magnetism of STO-based HS systems.