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Discussing the transport properties of powder-in-tube processed superconducting tapes based on the Bi-2223 and MgB2 compounds is presented. The transport properties of MgB2 tapes present different features depending on the thermo-mechanical treatment subjected to during the fabrication process.

A study describes newly fabricated, silver-sheathed Bi(2223) tapes where all the filaments can present a common misalignment angle with respect to the conductor plane. These tapes were produced using the four-roll deformation approach on a rectangular silver tube in which the individual filaments were stacked in a novel configuration. It will be shown that the superconducting filaments can be inclined and the maximum of the critical current density can be shifted to a desired angle with respect to the tape plane.

An evaluation of Ag sheathed tapes was conducted to study the temperature dependence of the intrinsic (BiPb)2Sr2Ca2Cu3O10 current density. A domain of the H-T plane was individuated where the current density is limited by the quality of the boundaries between neighboring grains by comparing transport and magnetic measurements performed on multifilamentary (Bi,Pb)2Sr2Ca2Cu3O10 tapes. The tape's behavior is similar to a granular superconductor while the domain behaved like a single crystal. The results showed that the intragrain current density is larger than the transport current density.

Two pulse laser ablation-fabricated artificial superlattices were studied to determine the correlation between structural disorder and transport properties of superlattices. Using reflection high energy electron diffraction and X-ray diffraction analyses, it was found that the 10% of doping cannot bring too much disorder to the structure and resistivity of the superlattices, nor can it induce metal insulator transition.

The use of ultrahigh vacuum laser ablation in producing borocarbide thin films has been studied. Laser ablation is better than magnetron sputtering since small targets can be easily changed. Fabricating samples with more than one rare earth element is also possible as is the preparation of buffer layers to optimize film growth. Results indicate the formation of strongly c-oriented superconducting films with rocking angles of 1 degree and smooth surfaces.