Effect of preloading on the relaxation of the levitation force in bulk Y-Ba-Cu-O superconductors

Y. Komano, E. Ito, K. Sawa, Y. Iwasa, T. Ichihara, Naomichi Sakai, I. Hirabayashi, Masato Murakami

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

We have studied the effect of preloading on the relaxation of the levitation force of bulk Y-Ba-Cu-O superconductors. The levitation force was measured by applying the external field with a superconducting solenoid. We set the standard magnetic induction (Bst) to be 1.2 T supposing that the bulk Y-Ba-Cu-O disk experiences this field in operation. Preloading was applied such that the external field was first ramped to 1.1Bst and reduced to Bst. We confirmed that the preloading was effective in reducing the relaxation of the levitation force, although the effective levitation force was largely depressed compared to that without preloading. The employment of an extra step to lower the field below Bst before reaching B st was effective in improving the effective levitation force without sacrificing the ability to reduce the relaxation rate. This is qualitatively understood in terms of the field distribution inside the disk based on the critical state model.

Original languageEnglish
Pages (from-to)789-793
Number of pages5
JournalPhysica C: Superconductivity and its Applications
Volume426-431
Issue numberI
DOIs
Publication statusPublished - 2005 Oct 1

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prestressing
YBCO superconductors
Electromagnetic induction
levitation
Solenoids
Superconducting materials
magnetic induction
solenoids

Keywords

  • Bulk superconductors
  • Flux flow
  • Levitation force
  • Shielding current distribution
  • Trapped magnetic field

ASJC Scopus subject areas

  • Condensed Matter Physics

Cite this

Effect of preloading on the relaxation of the levitation force in bulk Y-Ba-Cu-O superconductors. / Komano, Y.; Ito, E.; Sawa, K.; Iwasa, Y.; Ichihara, T.; Sakai, Naomichi; Hirabayashi, I.; Murakami, Masato.

In: Physica C: Superconductivity and its Applications, Vol. 426-431, No. I, 01.10.2005, p. 789-793.

Research output: Contribution to journalArticle

Komano, Y. ; Ito, E. ; Sawa, K. ; Iwasa, Y. ; Ichihara, T. ; Sakai, Naomichi ; Hirabayashi, I. ; Murakami, Masato. / Effect of preloading on the relaxation of the levitation force in bulk Y-Ba-Cu-O superconductors. In: Physica C: Superconductivity and its Applications. 2005 ; Vol. 426-431, No. I. pp. 789-793.
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AU - Ichihara, T.

AU - Sakai, Naomichi

AU - Hirabayashi, I.

AU - Murakami, Masato

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