MAGNETIC AND PHONONIC EXCITATIONS IN Y1-XPRXBA2CU3O7 FILMS

We present Raman spectra of Y1-xPrxBa2Cu3O7 (Y1-xPxBCO) thin films wit h various Pr contents on SrTiO3 substrates. Resonant and temperature d ependent studies are performed in A(1g) and B-1g polarization geometry . The phononic part of the spectra is used to analyze the stoichiometr ic and epitaxial quality of the samples. All films are c-axis oriented with a very high degree of in-plane orientation. Analyses of the phon on-line shapes show that a multi-phase composition of mixture-type fil ms (0.5 less than or equal to x < 1) cannot be excluded. Two-magnon ex citations visible in all samples are described within the framework of a damped Heisenberg antiferromagnet (HAFM). For both the exchange ene rgy J and the damping parameter Gamma we observe a linear dependence o n the Pr content. Unlike in single crystals, we do not observe a reson ant enhancement of the two-magnon peak intensity in PBCO.