Pulsed Laser Deposition of Thin YBCO Films on Faceted YSZ Single Crystal Fibers

Flexible rods of single crystals of 9% Y₂O₃-stabilized ZrO₂ (YSZ) were used as substrates for deposition of high-critical temperature superconducting (HTS) thin films. YSZ fibers were prepared by mini-pedestal method with laser heating and had average diameter of 300 micrometers and 30 mm length. X-ray diffraction analysis demonstrated high crystalline quality of obtained fibers and also indicated the presence of 15° deviation of the fiber axis from the [001] YSZ direction. Thin YBa₂Cu₃O_7−x films were grown by pulsed laser deposition on YSZ rods using CeO₂ buffer layer. Films have shown high critical temperature of 90 K with sharp superconducting transition. Critical current density was estimated to about 3×10⁴ A/cm² at 80 K. Temperature dependence of critical current density suggests granular structure of films with grain size about several microns. Our results demonstrate feasibility of flexible YSZ fibers coated by HTS thin films for practical use.