DocumentCode :
1073436
Title :
Bulk Superconducting Nano-Composites With High Critical Currents
Author :
Hari Babu, N. ; Iida, Kazumasa ; Briffa, Ansel ; Yun-Hua Shi ; Cardwell, David A.
Author_Institution :
Cambridge Univ., Cambridge
Volume :
17
Issue :
2
fYear :
2007
fDate :
6/1/2007 12:00:00 AM
Firstpage :
2953
Lastpage :
2956
Abstract :
Flux pinning sites are most effective if their size is comparable to the superconducting coherence length, which is on the nano-meter scale for RE-Ba-Cu-O superconductors [RE = rare earth element]. Introducing nano-phase inclusions directly into the bulk superconducting material has only been partially successful to date, however, due primarily to the absence of chemically stable phases that can co-exist with RE-Ba-Cu-O without suppressing its key superconducting properties. We have identified novel isostructural phases based on (RE)2Ba4CuMOy (where M = W, Zr, Nb, Ag and Bi) and have fabricated successfully superconducting bulk nano-composites with a high current carrying capability. The average size of the nano-inclusions is observed to vary from 20 nm to 300 nm depending on element M. An observed improvement in Jc under low and high external magnetic fields at 77 K correlates directly with an increased density of nano-inclusions in the superconducting matrix.
Keywords :
barium compounds; coherence length; critical currents; flux pinning; gadolinium compounds; high-temperature superconductors; inclusions; nanocomposites; samarium compounds; yttrium compounds; GdBaCuAgO - System; GdBaCuBiO - System; GdBaCuNbO - System; GdBaCuWO - System; GdBaCuZrO - System; SmBaCuAgO - System; SmBaCuBiO - System; SmBaCuNbO - System; SmBaCuWO - System; SmBaCuZrO - System; YBaCuAgO - System; YBaCuBiO - System; YBaCuNbO - System; YBaCuWO - System; YBaCuZrO - System; bulk superconducting nanocomposites; critical currents; flux pinning sites; high temperature superconductors; nanophase inclusions; rare earth element; size 20 nm to 300 nm; superconducting coherence length; temperature 77 K; Bismuth; Chemicals; Critical current; High temperature superconductors; Niobium; Superconducting magnets; Superconducting materials; Superconductivity; Yttrium barium copper oxide; Zirconium; Flux pinning; high temperature superconductors; melt-textured superconductors; nano-composites;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/TASC.2007.898223
Filename :
4278043
Link To Document :
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