Advertisement

Bulletin of Materials Science

, Volume 17, Issue 2, pp 153–162 | Cite as

Flux dynamics of YBCO/Ag composite

  • Indu Dhingra
  • B K Das
  • S C Kashyap
Article

Abstract

DC magnetization measurements have been carried out on bulk YBCO/Ag composites with silver content up to 20wt per cent. DC fields in the range 0·5 mT to 200 mT have been used to investigate the inter- and intragranular properties at 77K. The AC susceptibility as a function of temperature at different AC fields (0·026–0·30 mT) has also been studied. Under small DC fields (≈ 4 mT), depending on the Ag content andH max, the M-H loop shows a complicated behaviour. This behaviour can be explained on the basis of effect of strong field dependence of transport critical current, grain size and intragrain critical current densityJ cgm on low-field M-H loop. The estimation of intergranular critical current densityJ cjm from these loops does not remain a simple function of ΔM/d. The AC susceptibility measurements show a small increase inJ c(T) with silver content under low AC fields only, consistent with the transportJ c data; beyond thatJ c(T) decreases. This improvement inJ c(T) and transportJ c with silver can be ascribed to the improved coupling between grains but not to the pinning. Also at higher field (H max>20 mT) the addition of Ag decreases the intragrain critical current density. The upper critical field of intergranular regionH c2j and lower critical field of intragrain regionH c1g also decrease with silver content.

Keywords

Flux dynamics YBCO/Ag composite 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Aguillon C and Senoussi S 1990J. Less Common Metals 164–165 1061CrossRefGoogle Scholar
  2. Ambegaokar V and Baratoff A 1963Phys. Rev. B10 486Google Scholar
  3. Baliga S and Jain A L 1989Appl. Phys. A49 139Google Scholar
  4. Bean C P 1964Rev. Mod. Phys. 36 31CrossRefGoogle Scholar
  5. Calzona V, Cimberle M R, Ferdeghini C R, Putti M and Siri A S 1989Physica C157 425Google Scholar
  6. Dhingra I, Padam G K, Singh S, Tripathi R B, Rao S U M, Suri D K, Nagpal K C and Das B K 1991J. Appl. Phys. 70 1775CrossRefGoogle Scholar
  7. Dwir B, Affronte M and Pavuna D 1989Appl. Phys. Lett. 55 399CrossRefGoogle Scholar
  8. Goldfarb R B, Cross R W, Goodrich L F and Bergen N F 1993Cryogenics 33 3CrossRefGoogle Scholar
  9. Grover A K, Radhakrishnamurthy C, Chaddah P, Ravi Kumar G and Subba Rao G V 1988Pramana — J. Phys. 30 569Google Scholar
  10. Jung J, Mohamed M A K, Cheng S C and Franck J P 1990Phys. Rev. B42 6161Google Scholar
  11. Kim Y B, Hempstead C F and Strand A R 1963Phys. Rev. 129 528CrossRefGoogle Scholar
  12. Matsumoto Y, Hombo J, Yamaguchi Y and Nishida M 1990Appl. Phys. Lett. 56 1585CrossRefGoogle Scholar
  13. Maury R, Fert A R, Redoules J P, Ayache J, Sabras J and Monty C 1990Physica C167 591Google Scholar
  14. Pavuna D, Berger H, Affronte M, Maas J Van Der, Caponi J J, Guillot M, Lejay P and Tholence J L 1988Solid State Commun. 68 535CrossRefGoogle Scholar
  15. Ren Y, Meng J, Niu M and Zeng Z 1990Solid State Commun. 76 1103CrossRefGoogle Scholar
  16. Saito Y, Noji T, Endo A and Higuchi N 1987Jpn. J. Appl. Phys. 26 L832Google Scholar
  17. Sen S, Chen I G, Chen C H and Stefanescu D M 1989Appl. Phys. Lett. 54 766CrossRefGoogle Scholar
  18. Senoussi S, Ousenna M and Ribault M 1987Phys. Rev. B36 4003Google Scholar
  19. Singh J P, Leu H L, Poeppel R B, Voorhees E Van, Goudey G T, Winsley K and Shi D 1989J. Appl. Phys. 66 3154CrossRefGoogle Scholar
  20. Sridth S, Wu Dong Ho and Kennedy W 1989Phys. Rev. Lett. 63 1873CrossRefGoogle Scholar
  21. Tholence J L 1988Physica C153–155 1479Google Scholar
  22. Tiefel T H, Jin S, Sherwood R C, Davis M E, Kammlott G W, Gallagher P K, Johnson D W, Fastenacht R A Jr and Rhodes W W 1988Mater. Lett. 6 555Google Scholar
  23. Tinkham M and Lobb C J 1989Solid State Phys. 42 91CrossRefGoogle Scholar
  24. Xia J A, Ren H T, Zhao Y, Andrikidis C, Liu H K and Dou S K 1993Supercond. Sci. Tech. 6 315CrossRefGoogle Scholar
  25. Xu Y, Guan W, Zeibig K and Heiden C 1989Cryogenics 29 281CrossRefGoogle Scholar
  26. Yeshurun Y, Malozemoff A P, Holtzberg F and Dinger T R 1988Phys. Rev. B38 11828Google Scholar

Copyright information

© Indian Academy of Sciences 1994

Authors and Affiliations

  • Indu Dhingra
    • 1
  • B K Das
    • 1
  • S C Kashyap
    • 1
    • 2
  1. 1.Materials DivisionNational Physical LaboratoryNew DelhiIndia
  2. 2.Centre for Materials Science and TechnologyIndian Institute of TechnologyNew DelhiIndia

Personalised recommendations