RAMAN STUDIES IN OFF-STOICHIOMETRIC SUPERCONDUCTING COMPOUNDS OF THE TYPE BI2-XPBYSR2CA2CU3O-DELTA

Raman measurements performed on superconducting ceramic samples of the type Bi2-xPbySr2Ca2Cu3Odelta, with y = 0.3, 0.6, 0.9 and x = 0.1, 0.2 , are reported. All Raman phonons with symmetry A(1g) have been observ ed. Phonon identification has been carried out using previous reported studies of the Bi2Sr2Can-1CunO2n+y system, for n = 1, 2, 3. A descrip tion of the detected Raman active modes in all samples is given, and t he study of these modes in terms of the relative amount of lead-to-bis muth content and thermal treatment is also presented.