A structure is provided and includes (i) a substrate having a surface, the surface comprising a ternary or quaternary oxide having a first lattice parameter, the first lattice parameter being a lattice parameter of the ternary or quaternary oxide as it is present at the surface; and (ii) a layer of a perovskite oxide on the ternary or quaternary oxide, the perovskite oxide having a second lattice parameter, the second lattice parameter being a native lattice parameter of the perovskite oxide, wherein the first lattice parameter is larger than the second lattice parameter. A method for forming a perovskite oxide with an a-axis orientation is also provided.