Evidence of oxygen content heterogeneity in TSMTG YBa2Cu3O7 − δ/Y2BaCuO5 composites by micro-Raman spectrometry

Abstract : The homogeneity of the oxygen content of TSMTG-YBa2Cu3O7 − δ/Y2BaCuO5 composites has been investigated by micro-Raman spectrometry. The Y123 compound has been found to be very sensitive to the laser power, but a laser power of 0.04 mW has been shown to not to be harmful for the samples, even after 2 h of irradiation. Raman spectra have shown that the oxygen content of YBa2Cu3O7 − δ/Y2BaCuO5 ceramics is not homogeneous at the micrometer scale. In addition, no monotonic decrease of the oxygen content is observed from the periphery to the core of the sample, confirming that the oxygen uptake is not strictly controlled by a diffusion process.