DocumentCode :
1526956
Title :
Superconducting properties of Nd-Ba-Cu-O thick films prepared by liquid phase epitaxial growth
Author :
Takagi, A. ; Mizutani, U. ; Kitamura, T. ; Taniguchi, S. ; Shiohara, Y. ; Hirabayashi, I. ; Tanaka, S. ; Yamada, Y.
Author_Institution :
Dept. of Crystalline Mater. Sci., Nagoya Univ., Japan
Volume :
7
Issue :
2
fYear :
1997
fDate :
6/1/1997 12:00:00 AM
Firstpage :
1388
Lastpage :
1391
Abstract :
C-axis oriented Nd/sub 1+x/Ba/sub 2-x/Cu/sub 3/O/sub y/ thick films were grown by the liquid phase epitaxy (LPE) technique onto MgO (100) single crystal substrates in Ar gas atmosphere containing 0.5 at.% O/sub 2/. The superconducting transition temperature T/sub c/ was very broad, when the film thickness was 10 /spl mu/m but became very sharp when it was increased to 100 /spl mu/m. The T/sub c/ value for the 100 /spl mu/m thick film could be increased up to 92 K by post-annealing at 300/spl deg/C for 336 hrs in O/sub 2/ atmosphere. Moreover, the peak effect, which is characterized by an increase in magnetisation with increasing magnetic field up to 15000 G at 50 K, was observed in the 100 /spl mu/m thick film. A substantial improvement in the superconducting properties when the film thickness is increased to 100 /spl mu/m, can be attributed to the stable persistence of the steady state growth mode instead of the transient mode responsible for the first 10 /spl mu/m thick deposition.
Keywords :
annealing; barium compounds; crystal orientation; high-temperature superconductors; liquid phase epitaxial growth; magnetisation; neodymium compounds; superconducting epitaxial layers; superconducting transition temperature; 10 to 100 mum; 300 C; 336 h; 50 K; 92 K; Ar; Ar gas atmosphere; LPE; MgO; MgO (100) single crystal substrates; Nd-Ba-Cu-O thick films; NdBa/sub 2/Cu/sub 3/O/sub 7/; O/sub 2/; T/sub c/; c-axis oriented Nd/sub 1+x/Ba/sub 2-x/Cu/sub 3/O/sub y/ thick films; film thickness; liquid phase epitaxial growth; magnetic field; magnetisation; peak effect; post-annealing; steady state growth mode; superconducting properties; superconducting transition temperature; transient mode; Argon; Atmosphere; Epitaxial growth; Magnetization; Neodymium; Substrates; Superconducting epitaxial layers; Superconducting films; Superconducting transition temperature; Thick films;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/77.620829
Filename :
620829
Link To Document :
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