Abstract
Measurements of flux creep have been undertaken for a variety of superconductors' to determine the factors that control the temperature and magnetic field regimes where the material transforms from a strong-pinning rigid-flux lattice material to the region where the flux lattice is highly mobile. Analysis of the data in terms of a single effective pinning potential, U/sub eff/, using the Beasley model indicates that all of the superconductors measured have a gradual transition from the strong pinning behavior at low temperature to weak pinning behavior at high temperature. There is a narrow band of fields and temperatures in the H-T plane where U/sub eff//kT rises from 2 to 100. The position of this band changes considerably from material to material. It is shown that there are some striking similarities and some clear trends in the pinning potentials when they are plotted on a reduced temperature scale. The highly anisotropic Tl-based and Nd-based copper oxides are very similar even though their T/sub c/ values differ by a factor of 5. In the progression from Nb-Ti to the cubic Bi-oxide to the anisotropic Cu-oxide, there is a clear trend to a wider region of high flux creep.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.