Title :
Surface impedance studies of the high-Tc oxide superconductors
Author :
Hylton, T.L. ; Beasley, M.R. ; Kapitulnik, A. ; Carini, John P. ; Drabeck, Lawrence ; Grunner, G.
Author_Institution :
Dept. of Appl. Phys., Stanford Univ., CA, USA
fDate :
3/1/1989 12:00:00 AM
Abstract :
The authors briefly review results of measurements of the multimeter-wave surface impedance of ceramic, thin-film and single-crystal samples of the high-Tc oxide superconductors. The observed losses and temperature dependences do not agree with BCS (Bardeen-Cooper-Schriefer) theory. The authors discuss recent measurements of single-crystal B2CaSr2Cu 2Ox and the effect of the application of a perpendicular magnetic field. They consider the possibilities of intrinsic and defect mechanisms to explain the observations. In particular, they discuss the effects of weakly coupled granular films on surface impedance. It is concluded that better samples are necessary to resolve the issue of the source of the large values of the surface impedance observed thus far
Keywords :
bismuth compounds; calcium compounds; electric impedance measurement; high-temperature superconductors; microwave measurement; strontium compounds; superconducting thin films; B2CaSr2Cu2Ox; BCS theory; Bardeen Cooper Schriefer theory; EHF; ceramic samples; defect mechanisms; effects of weakly coupled granular films; high temperature superconductor; high-Tc oxide superconductors; intrinsic mechanisms; losses; multimeter-wave surface impedance; single-crystal samples; surface impedance; surface impedance measurement; temperature dependences; thin film samples; Ceramics; Copper; Electrical resistance measurement; Magnetic films; Superconducting films; Superconducting transition temperature; Superconductivity; Surface impedance; Surface resistance; Temperature dependence;
Journal_Title :
Magnetics, IEEE Transactions on
