Thermal conductivity of YBCO coated conductors fabricated by IBAD-PLD method

We have measured the temperature dependence of the thermal conductivity kappa (T) of YBCO coated conductor tapes with various thicknesses of stabilizing Ag layer and analyzed the measured kappa(T) using the equivalent heat current circuit. kappa(T) of the tape increased with increasing thickness of Ag layer. In the analysis, the dominant thermal carriers were found to be the electrons in the Ag layer in the entire temperature range. The thermal conductivity of the Ag layer, kappa(Ag)(T), was estimated to decrease with increasing thickness of Ag layer, which suggested that impurities and/or crystal defects were introduced during the long time deposition of Ag.