NUOVO CIMENTO DELLA SOCIETAÌ€ ITALIANA DI FISICA. D CONDENSED MATTER, ATOMIC, MOLECULAR AND CHEMICAL PHYSICS, BIOPHYSICS
Abstract
An X-ray photoelectron spectroscopy study of Na-doped Bi-2212 cuprates is reported. Core level photoemission spectra were collected, at different take-off angles, from a monophasic crystal. The results of the lineshape analysis and the dependence of the core line intensity on the analyser take-off angle allowed us to rule out the presence of Na within the Bi-O layers, indicating that Na+ is very likely replacing Ca2+ or Si2+ ions.
