A current-density scale for characterizing nonlinearity in high-Tc superconductors
Kenneth Leong, James C. Booth, Susan A. Schima
In this paper, we characterize microwave nonlinearity in a high temperature superconducting (HTS) thin film sample by measurement of a geometry-independent current-density scale jo. This quanity j specifies the strenth of a material-dependent nonlinearity, and can be used to estimate the nonlinear microwave response of planar superconducting transmission-line devices. Our procedure for measurements of joinvolves microwave measurements on superconducting coplanar waveguide devices patterned onto the HTS sample. In a YBa2Cd^3^07-x (YBCO) sanokem we obtained a maximum experimental value in joof approximately 3.26x108 A/cm2 at 25 k. From the measured temperature-dependence of jo in our YBCO sample, and assuming a theoretical pair-breaking current density jc equal to 3x108 A/cm^u, we calculated the temperature dependence of the quasiparticle factor b(t). The curve of the experimentally-obtained b(t) matched well with a theoretically-predicted behavior in the scenario of D-wave symmetry in the superconducting order parameters
, Booth, J.
and Schima, S.
A current-density scale for characterizing nonlinearity in high-Tc superconductors, Applied Superconductivity Conference, Jacksonville, FL, [online], https://doi.org/10.1109/TASC.2005.849371
(Accessed March 2, 2024)