We were successful in synthesizing non-linear YBa 2 Cu 3 Ox whiskers, i.e. half loops or kinked shapes, which are promising candidates for solid-state devices based on the intrinsic Josephson effect and with improved electrical connections. We report on a complete characterization of their structural properties via a synchrotron nanoprobe as well as laboratory single-crystal diffraction techniques. This investigation allowed us to fully disclose the growth mechanism, which leads to the formation of curved whiskers. The superconducting properties are evaluated in comparison with their straight counterpart, revealing a strong functional analogy and confirming their potential applicability in superconducting electronic devices.

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Al(+3)-doped (Y,Ca)Ba2Cu3O(7-y) (YBCO) whiskers have been synthesized using a solid-state reaction technique. These materials are promising candidates for solid-state THz applications based on sequences of Josephson Junctions (IJJs). Alumina addition was systematically varied and the effect of aluminium incorporation on the structure has been investigated using single-crystal X-ray diffraction. Aluminium only replaces Cu atoms in the O-Cu-O-Cu chains and a gradual transition from orthorhombic to tetragonal space group occurs, thus increasing the Al content. A gradual modification of the coordination sphere of the copper site has also been observed. The Ca(2+) ion substitutes mainly the Y(3+) ion and also, to a small extent, the Ba(2+) ion.