Title :
Superconducting tapes with critical current density of 104 A/cm2 at 77 K and zero magnetic field
Author :
Narumi, E. ; Song, L.W. ; Hwa, S. ; Ye, J. ; Yang, F. ; Kao, Y.H. ; Patel, S. ; Shaw, D.T. ; Rkaczyk, J.E.
Author_Institution :
New York State Inst. on Superconductivity, State Univ of New York, Buffalo, NY, USA
fDate :
3/1/1991 12:00:00 AM
Abstract :
A critical current density above 104 A/cm2 at 77 K and zero magnetic field has been achieved for both YBa2 Cu3O6.8 (YBCO) thin films on metallic substrates and Bi-based superconducting films on silver tapes. A transition buffer, consisting of subbuffers deposited at different temperatures, was used to enhance the crystallinity and the transport properties of YBCO films on metallic substrates. YBCO films were fabricated using in-situ laser deposition, and they were strongly c-axis oriented. A critical temperature of 87 K and a critical current density of 3×104 A/cm2 at 77 K were obtained for a 0.5-μm-thick YBCO film. The magnetic field dependence of Jc could be increased by using Pt-coated metallic substrates. For 10-20-μm-thick Bi-based superconducting tape, by using a brush-on technique and heat treatment, a critical current of 104 A/cm 2 at 77 K was obtained. This tape showed strong magnetic flux pinning at low temperature
Keywords :
barium compounds; critical current density (superconductivity); flux pinning; high-temperature superconductors; superconducting junction devices; superconducting thin films; superconducting transition temperature; yttrium compounds; BiSrCaCuO; YBa2Cu3O6.8; brush-on technique; c-axis oriented; critical current density; critical temperature; crystallinity; high temperature superconductor; laser deposition; magnetic field dependence; metallic substrates; strong magnetic flux pinning; tapes; transport properties; Critical current density; Crystallization; Magnetic fields; Magnetic films; Silver; Substrates; Superconducting films; Superconducting thin films; Superconducting transition temperature; Yttrium barium copper oxide;
Journal_Title :
Magnetics, IEEE Transactions on
