Doping Effect on the Magnon Scattering Spectrum of (Eu,Ce)2(Ba,Eu)2Cu3O8+z

We have investigated the carrier concentration dependence of the Raman scattering spectra, using the single crystals of (Eu,Ce)2(Ba,Eu)2Cu3O8+z. We prepared several samples with various oxygen contents by annealing fully oxygenated samples with Tc=30K in N2-atmosphere at various temperatures. The two magnon peak was clearly observed in the lowest oxygen content sample. With increasing oxygen content, the magnon peak gradually disappeared and the spectral weight moved towards lower energy. This magnon behavior is the same as that observed in the other hole-doped high-Tc superconducting cuprates, and is clearly different from the electron-doped one.