METAL DOPING EFFECTS IN NIR RAMAN-SPECTRA OF YBCO EPITAXIAL-FILMS

Metal doping (Co, Zn) of YBCO epitaxial thin films leads to large chan ges of the scattering efficiencies of various lattice modes in near-in frared (NIR) - Raman spectra (1064 nm) if it is accompanied by a varia tion of the charge carrier concentration. The results resemble earlier observations in oxygen depleted YBCO thin films. In contrast, no effe ct is found when metal doping does riot change the carrier concentrati on even if it leads to a massive T-c suppression.