Structure of Superconducting [BaCuOx]2/[CaCuO2]n Superlattices on SrTiO3(001) Investigated by X-ray Scattering

Abstract

Structural properties of [BaCuOx]2/[CaCuO2]n superconducting superlattices with a number of CaCuO2 layers ranging between 2 and 3 were investigated using synchrotron radiation, by coplanar (symmetrical and asymmetrical) X-ray diffraction and also in grazing incidence geometry. This extensive X-ray diffraction characterisation allowed to confirm the pseudomorphic growth of [BaCuOx]2/[CaCuO2]n superlattices on the SrTiO3 (001)-oriented substrate. Reciprocal space maps in symmetrical configuration, i.e. by specular reflection, showed the effect of a slight miscut of the substrate on the inclination of the rods. Finally, the interface and surface morphology were investigated by diffuse scattering obtaining the in-plane and out-of-plane correlation properties of the interface roughness and these results were compared with the surface roughness measured by atomic force microscopy.