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Commercial alumina templates as base to fabricate 123‐type high‐ T c superconductor nanowires
Author(s) -
Koblischka M. R.,
Zeng X. L.,
Hartmann U.
Publication year - 2016
Publication title -
physica status solidi (a)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.532
H-Index - 104
eISSN - 1862-6319
pISSN - 1862-6300
DOI - 10.1002/pssa.201532475
Subject(s) - template , nanowire , superconductivity , materials science , anodizing , scanning electron microscope , squid , nanotechnology , template method pattern , electrical resistance and conductance , chemical engineering , analytical chemistry (journal) , condensed matter physics , composite material , chemistry , aluminium , ecology , physics , engineering , biology , chromatography
Nanowires of high‐ T c superconductors of the RE‐123 type (RE = rare earths) were grown by the anodized alumina template method, employing commercially available alumina templates with nominal pore diameters of 20 and 100 nm. Pre‐reacted YBa 2 Cu 3 O x (YBCO) and NdBa 2 Cu 3 O x (NdBCO) powder was molten on top of the templates in order to fill the pores with the 123‐type material. The resulting samples were oxygen‐annealed at 450 °C. Superconductivity with a transition temperature of 88 K (YBCO) and 96 K (NdBCO) was confirmed by means of magnetic susceptibility measurements (SQUID) using pieces of the filled template. The electric (resistance) and magnetic measurements revealed further relatively sharp superconducting transitions. To understand the dimensions of the resulting nanowires (length up to 10 μm, diameter between 100 and 250 nm), which do not correspond to the nominal pore diameters, the empty and filled commercial templates were analyzed in detail by scanning electron microscopy. We discuss the feasibility of this approach to produce larger amounts of nanowires.