Title :
Measurements of low magnetic field microwave absorption in 110-K superconducting Bi-Sr-Ca-Cu-O thin films
Author :
Kula, W. ; Sobolewski, R.
Author_Institution :
Dept. of Electr. Eng., Rochester Univ., NY, USA
fDate :
3/1/1993 12:00:00 AM
Abstract :
Studies on magnetic-field dependent microwave absorption in Bi(Pb)-Sr-Ca-Cu-O thin films superconducting above 100 K are reported. The films were DC magnetron sputtered on MgO and CaNdAlO/sub 4/ single crystals from Pb-rich targets and post-annealed at high temperatures in air for less than 1 h. The measurements were performed as a function of temperature, DC magnetic field, and the film magnetic history. The results show that the microwave absorption measurements are a very sensitive tool for high-T/sub c/ thin-film characterization, since even small variations in the film phase homogeneity, granularity, or crystalline orientation are clearly visible on the modulated absorption curves. It was found that the films characterized by the lowest absorption exhibited the highest critical current densities.<>
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); electromagnetic wave absorption; high-temperature superconductors; lead compounds; sputtered coatings; strontium compounds; 110 K; Bi-Sr-Ca-Cu-O thin films; BiPbSrCaCuO; CaNdAlO/sub 4/; DC magnetic field; DC magnetron sputtered; MgO; characterization; critical current densities; crystalline orientation; film magnetic history; granularity; high temperature superconductor; high temperatures; low magnetic field microwave absorption; phase homogeneity; post-annealed; Electromagnetic wave absorption; High temperature superconductors; Magnetic field measurement; Magnetic films; Microwave measurements; Sputtering; Superconducting magnets; Superconducting microwave devices; Superconducting thin films; Temperature sensors;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
