Magnetic properties of fluorinated Pb-doped Hg-1223 high T/sub c/ superconductors

Fluorination of Pb-doped HgBa/sub 2/Ca/sub 2/Cu/sub 3/O/sub y/ (Hg-1223) system was investigated. Structural and magnetic measurements reveal that fluorine addition promotes the phase formation, optimize the charge carrier concentration, and enhance flux pinning. We report an increase in both the transition temperature and the critical current density through controlled fluorine incorporation. Even a possible change in the pinning mechanism in this technologically important system is suggested.