Microstructure and interface studies of LaVO3/SrVO3 superlattices

The structure and interface characteristics of (LaVO3)(6m)(SrVO3)(m) superlattices deposited on a (100)-SrTiO3 substrate were studied using transmission electron microscopy (TEM). Cross-section TEM studies revealed that both LaVO3 (LVO) and SrVO3 (SVO) layers are good single-crystal quality and epitaxially grown with respect to the substrate. It is evidenced that LVO layers are made of two orientational variants of a distorted perovskite compatible with bulk LaVO3, while SVO layers suffers from a tetragonal distortion due to the substrate induced stain. Electron energy loss spectroscopy investigations indicate changes in the fine structure of the V L-23 edge, related to a valence change between the LaVO3 and the SrVO3 layers.