Structural ordering and chemical configuration of Ba-based infinite-layer superlattices

In this work, we present a detailed structural and microanalytical study of BaCuO2/CaCuO2 superlattices grown on (001) SrTiO3 substrates by pulsed laser deposition technique. Our analyses were performed by using high-resolution x-ray diffraction, reciprocal space mapping, x-ray specular reflectivity, and x-ray photoelectron spectroscopy. We found that the BaCuO2/CaCuO2 superlattices are grown pseudomorphically on the SrTiO3 substrate. X-ray photoelectron spectroscopy measurements show that the Ca is partially oxidized having both Ca-O and Ca-Ca bonds, while Ba is completely oxidized (Ba-O bonds), The results of our analyses demonstrate that the pulsed laser deposition technique allows one to fabricate high quality infinite-layer superlattices of high structural and chemical ordering.