Magnetic properties of thin Ni films measured by a dc SQUID-based magnetic microscope

We have applied a scanning HTS (high-temperature superconductor) de SQUID (superconducting quantum interference device) -based magnetic microscope to study the magnetic properties of Au/Ni/Si(100) films in the thickness range from 8 to 200 Angstrom at T = 77 K. A one-domain structure with in-plane orientation of the magnetic moment was found for film thicknesses exceeding 26 Angstrom. A drastic decrease of the magnetization of the film was detected when the thickness is less than 26 Angstrom

Pulsed laser deposition of thin YBCO films on faceted YSZ single crystal fibers

Flexible rods of single crystals of 9% Y2O 3-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 YBa2Cu3O7-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/cm 2 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

BOUNDARY CONDITIONS FOR THE USADEL EQUATIONS AND PROPERTIES OF DIRTY S-N-S SANDWICHES

Il est démontré que les conditions aux limites pour les équations d'Usadel dans le cas d'une limite plane consistent en la continuité de F et [MATH]. Ces conditions sont utilisées pour l'obtention des conditions aux limites effectives à l'interface S-N pour les équations de Guinzbourg-Landau, aussi bien que pour l'obtention de la relation courant-phase d'une jonction Josephson S-N-S, ayant un faible libre parcours moyen.Boundary conditions for the Usadel equations at a plane wall conducting interface found to consist in continuity of F and [MATH]. These conditions are used to find the effective boundary conditions for the Ginzburg-Landau equations at the S-N interface, as well as the current-phase relationship for S-N-S sandwiches with a short electron mean free path