Title :
Temperature dependence of the surface resistance R(T,/spl omega/) and mean free path l(T) of YBCO-superconductors
Author :
Jacobs, T. ; Numssen, K. ; Schwab, R. ; Heidinger, R. ; Halbritter, J.
Author_Institution :
Inst, fur Materialforschung, Forschungszentrum Karlsruhe, Germany
fDate :
6/1/1997 12:00:00 AM
Abstract :
The surface resistance R(T/spl omega/) at 10 and 145 GHz is obtained experimentally between 4 and 300 K. In the temperature range T/sub a//spl les/T/spl les/T/sub c/ R(T) is quantitatively fitted by the BCS theory with a mean free path l(T) increasing exponentially below T/sub c/. The l(T)-increase is related to diminishing plane-chain scattering and is limited at T/sub a/ by "inelastic surface scattering" at weak or strong links, e.g., at twin boundaries of an average distance a/sub TW/. They dominate scattering for l(T)/spl ges/a/sub TW//2. Below T/sub a/ the enforced energy transfer from YBCO-crystallites to weak links enhances R(T\n\n\t\t
Keywords :
BCS theory; barium compounds; carrier mean free path; crystallites; electric impedance; high-temperature superconductors; surface conductivity; twin boundaries; yttrium compounds; 10 to 145 GHz; 4 to 300 K; BCS theory; YBCO; YBa/sub 2/Cu/sub 3/O/sub 7/; crystallites; enforced energy transfer; inelastic surface scattering; mean free path; plane-chain scattering; strong links; surface impedance; surface resistance; temperature dependence; weak links; Crystals; Grain boundaries; Impedance measurement; Scattering; Superconducting films; Superconductivity; Surface impedance; Surface resistance; Temperature dependence; Zirconium;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
