Power dependencies of the surface impedance of Y-Ba-Cu-O

Author

Halbritter, J. ; Numssen, K. ; Gaganidze, E.

Author_Institution

Forschungszentrum Karlsruhe, Germany

Volume

11

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

3541

Lastpage

3544

Abstract

The application of HTS is obstructed by the nonlinear behavior of Z(T,f,H_rf) with rf field. The study of those nonlinearities profits by carefully calibrated rf measurements in the frequency and time domain, which yield δR_S(H)∝Hⁿ∝_S(H). In contrast to δR_S(H)∝Hⁿ, the ratio r=δX_S/δR_S is independent of geometry factor and shows distinct T and f dependencies for various mechanisms and rf set-ups. The high power rf response in the frequency domain yields nonlinear resonance curves, n and r values. The time domain measurements give useful insight about dynamics of the underlying nonlinear mechanisms. The results r≈1 and n≈1-2 are in line with Josephson fluxons in weak links, which may interact with dc fluxons threading through the weak links

Keywords

Josephson effect; barium compounds; flux-line lattice; frequency-domain analysis; high-frequency effects; high-temperature superconductors; surface conductivity; time-domain analysis; yttrium compounds; Josephson fluxons; Y-Ba-Cu-O; YBa₂Cu₃O₇; dc fluxons; frequency domain; geometry factor; high power rf response; nonlinear behavior; nonlinear resonance curves; power dependencies; rf field; rf measurements; surface impedance; time domain; weak links; Couplings; Frequency domain analysis; Frequency measurement; Geometry; High temperature superconductors; Resonance; Surface impedance; Surface resistance; Time measurement; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.919828

Filename

919828