Speaker
Prof.
Tatiana Prikhna
(Institute for Superhard Materials of the National Academy of Sciences of Ukraine)
Description
The results of the investigations of crystal structure, phase composition, relief, and superconducting characteristics of the oxygen-containing thin films from magnesium diboride (MgB2), which are deposited on the dielectric wafers by a magnetron sputtering of the magnesium diboride targets, are presented. It has been demonstrated that depending on the parameters of the deposition and annealing processes the thin films with various degrees of the structure perfection and phase composition could be fabricated. The various combinations of the Abrikosov vortices pinning types could be realized in the films such as a pinning in the places of fluctuation of superconducting critical temperature (δТс -type) or a pinning in the places of fluctuation of the free path length (δl-type). The appearance and density of these fluctuations can be influenced by the synthesis conditions. We obtained the deposited superconducting thin films, the structure of which can be described as MgBxОу and is in fact a solid solution of oxygen in the magnesium diboride crystal lattice. The density of superconducting critical currents of these films attains 1.8•1011 – 8.2 • 1010А/м2 at 10 К and 8•1010 – 2.8 • 1010А/м2 at 20 К in the 0–1 Т fields (if an external magnetic field is oriented in parallel to the wafer surface) .
Author
Prof.
Tatiana Prikhna
(Institute for Superhard Materials of the National Academy of Sciences of Ukraine)
Co-authors
Dr
Andrey Shapovalov
(Institute for Superhard Materials of the National Academy of Sciences of Ukraine)
Mr
Anton Shaternik
(Institute for Superhard Materials of the National Academy of Sciences of Ukraine)
Dr
Michael Eisterer
(Atominstitut, Vienna University of Technology)
Mr
Valeriy Kovylaev
(Institute for Problems in Material Science, NAS Ukraine)
Dr
Vladimir Shaternik
(G. V. Kurdyumov Institute for Metal Physics of the N.A.S. of Ukraine)
Dr
Wilfried Goldacker
(Karlsruhe Institute of Technology)
