Dependence of positron lifetime parameters on the preparation techniques and structural defects for YBCO cuprates

Abstract

Based on possible existence of technique effect and scattered distribution in positron results, a special investigation was made for YBa 2Cu 3O 7− δ systems in this paper. The dependence of preparation techniques and the structural characteristics on the sintering temperature and time are also given by positron lifetime, XRD and SEM experiments. The results show that the positron lifetime parameters and the microstructure show a significant dependence on sintering temperature and time. It is proved that, in the range of 920–950 °C/12–72 h, the positron results have good stability and reliability in the sintering times and temperature. The distribution characteristic of defect was evaluated and had a good stability in the preparation technique. The present studies provide an important experimental evidence for the study of Y-123 systems by positron experiment.