X‐ray emission studies on the (La_{1 − x}Ba_x)₂CuO_{4 ± y} system

Abstract

X‐ray emission spectroscopy was used to establish the valency of Cu in the superconducting (La1‐xBax)2CuO4±y (LBCO) system. Samples were prepared by both solid‐state diffusion and coprecipitation methods. It was observed that diffusion is faster and mixing is more intimate in the coprecipitated sample. A definite shift in the Cu K emission was also observed in samples such as CuO, La2CuO4 and LBCO. It was observed that the valency of copper in the LBCO system is equal to or greater than 2. Further, Ba has been found to play a major role in the emission process. The La emission spectra remained the same for all the samples studied. SEM and XRD studies indicated the presence of a two‐phase structure of the compound.