The surface characterization and stability of Pb-doped Hg-based HTSC

Abstract The stability of the homologous series of mercury copper oxide superconductors is still a serious problem that receives attention from scientists all over the world. In this paper, we show that Pb-doping in Hg-1223 can improve the thermal stability of the system. The transition temperature, as well as the flux pinning effect of the system can be enhanced. The surface characterization was performed by means of Auger electron spectroscopic (AES), X-ray photoelectron spectroscopic (XPS) and sputtered neutral-particle mass spectroscopic analyses (SNMS). The results of our experiment indicate that the Pb-enriched regions, together with the Hg deposition on the surface of the ceramic sample, play the role of flux pinning centres to resist the flux creep.