EXCESS MAGNETIZATION DUE TO INTERFILAMENTARY PROXIMITY COUPLING IN NB-TI MULTIFILAMENTARY WIRES

被引:38
作者
HARADA, N [1 ]
MAWATARI, Y [1 ]
MIURA, O [1 ]
TANAKA, Y [1 ]
YAMAFUJI, K [1 ]
机构
[1] FURUKAWA ELECTRON CO LTD,YOKOHAMA RES & DEV LABS,YOKOHAMA 220,JAPAN
关键词
SUPERCONDUCTING MAGNETS; MULTIFILAMENTARY WIRES; PROXIMITY EFFECTS; TWIST PITCH; JOSEPHSON WEAK LINKS;
D O I
10.1016/0011-2275(91)90175-V
中图分类号
O414.1 [热力学];
学科分类号
摘要
It is shown theoretically that the excess magnetization of a multifilamentary superconducting wire caused by interfilamentary proximity coupling, DELTA-M(p), is proportional to the twist pitch of the wire, 1. It is also shown that this theoretical prediction can be confirmed experimentally for Nb - Ti multifilamentary wires. The critical current density of the super-conducting shielding current flowing through the matrix, which becomes a weak superconductor due to interfilamentary proximity coupling, is given by J(cp) = J(o)(B/B(c2p))-1.4 x [1 - (B/B(c2p)]1.4 with J(o) infinity [cosh(d(N)/2xi-N)]-2, where B is the magnetic flux density, and B(c2p)'xi-N and d(N) are the upper critical flux density, the effective coherence length and the width of the weakly superconducting matrix, respectively. It is concluded that DELTA-M(p) can be estimated quantitatively by measuring the 1 dependence of total magnetization, and also that the most effective method of decreasing DELTA-M(p) is to decrease xi-N to the dirty limit.
引用
收藏
页码:183 / 191
页数:9
相关论文
共 17 条
[1]   MAGNETIZATION OF HIGH-FIELD SUPERCONDUCTORS [J].
BEAN, CP .
REVIEWS OF MODERN PHYSICS, 1964, 36 (1P1) :31-+
[2]   EFFECT OF TWIST ON WIRES MADE FROM INSITU SUPERCONDUCTORS [J].
CARR, WJ .
JOURNAL OF APPLIED PHYSICS, 1983, 54 (11) :6549-6552
[3]  
CARR WJ, 1983, AC LOSS MACROSCOPIC, P91
[4]  
DEUSCHER G, 1969, SUPERCONDUCTIVITY, P1005
[5]   NBTI WIRES WITH ULTRA-FINE FILAMENTS FOR 50-60 HZ USE - INFLUENCE OF THE FILAMENT DIAMETER UPON LOSSES [J].
DUBOTS, P ;
FEVRIER, A ;
RENARD, JC ;
TAVERGNIER, JP ;
GOYER, J ;
KY, HG .
IEEE TRANSACTIONS ON MAGNETICS, 1985, 21 (02) :177-180
[6]   MICROWAVE STUDY OF PROXIMITY EFFECTS IN SUPERCONDUCTIVITY [J].
FISCHER, G ;
KLEIN, R .
PHYSIK DER KONDENSITERTEN MATERIE, 1968, 7 (01) :12-+
[7]   THE EFFECT OF MAGNETIC-IMPURITIES AND BARRIERS ON THE MAGNETIZATION AND CRITICAL CURRENT OF FINE FILAMENT NBTI COMPOSITES [J].
GHOSH, AK ;
SAMPSON, WB ;
GREGORY, E ;
KREILICK, S ;
WONG, J .
IEEE TRANSACTIONS ON MAGNETICS, 1988, 24 (02) :1145-1148
[8]   ANOMALOUS LOW FIELD MAGNETIZATION IN FINE FILAMENT NBTI CONDUCTORS [J].
GHOSH, AK ;
SAMPSON, WB ;
GREGORY, E ;
KREILICK, TS .
IEEE TRANSACTIONS ON MAGNETICS, 1987, 23 (02) :1724-1727
[9]   MAGNETIC-FIELD DECAY IN MODEL SSC DIPOLES [J].
GILBERT, WS ;
ALTHAUS, RF ;
BARALE, PJ ;
BENJEGERDES, RW ;
GREEN, MA ;
GREEN, MI ;
SCANLAN, RM .
IEEE TRANSACTIONS ON MAGNETICS, 1989, 25 (02) :1459-1462
[10]  
GILBERT WS, 1990, ADV CRYOGENIC ENG A, V36, P223