Preventing the Reconstruction of the Polar Discontinuity at Oxide Heterointerfaces

摘要

Perovskite oxide heteroepitaxy receives much attention because of the possibility to combine the diverse functionalities of perovskite oxide building blocks. A general boundary condition for the epitaxy is the presence of polar discontinuities at heterointerfaces. These polar discontinuities result in reconstructions, often creating new functionalities at the interface. However, for a significant number of materials these reconstructions are unwanted as they alter the intrinsic materials properties at the interface. Therefore, a strategy to eliminate this reconstruction of the polar discontinuity at the interfaces is required. We show that the use of compositional interface engineering can prevent the reconstruction at the La_(0.33)Sr_(0.67)MnO_3/SrTiO_3 (LSMO/STO) interface. The polar discontinuity at this interface can be removed by the insertion of a single La_(0.33)Sr_(0.67)O layer, resulting in improved interface magnetization and electrical conductivity.