High-K strontium titanate and lanthanum nickelate based epitaxial heterostructures and their structural characterization

Epitaxial bilayer heterostructures of high-k strontium titanate (SrTiO
3
) and lanthanum nickelate (LaNiO
3
) on (100) oriented lanthanum aluminate (LaAlO
3
) substrates were fabricated using pulsed laser deposition. Their structural characterization by high resolution x-ray diffraction (HR-XRD) confirmed the single phase, out of plane c-axis oriented epitaxial growth. Such that, a lattice misfit between SrTiO
3
and LaNiO
3
caused a compressive in-plane lattice strain in this heterostructure. Subsequently, interfacial characterization by x-ray reflectivity (XRR) confirmed their high quality growth with 0.8063 nm interfacial roughness.