Reduction of flux-creep in magnetized bulk HTS by use of permanent magnets. (15th November 2016)

• Record Type: Journal Article
• Authors: Parks, D; Weinstein, R; Davey, K; Sawh, R-P; Carpenter, K
• Is Part Of: Superconductor science & technology. Volume 30:Number 1(2017:Jan.)
• Publication Date: 2016-11-15
• Subjects: reduction of flux-creep -- effect of permanent magnet on flux-creep -- applied field reduction of flux-creep; Superconductivity -- Periodicals; Superconductors -- Periodicals; 537.623
• DOI: 10.1088/0953-2048/30/1/015011
• Languages: English
• ISSNs: 0953-2048

Abstract

Abstract: We report the effect of permanent magnet (PM) collars on the flux-creep rate of magnetized bulk HTS. The creep rates of single-grain, cylindrical samples are measured with attached collars activated to various fields, B PM, in the range 0 ≤ B PM ≤ B PM, max, where B PM, max is the fully saturated field of the PM. As B PM varies, the creep rate of the HTS is found to maintain its well-known form—a constant fractional loss λ, of original residual field, per decade of time. However, the magnitude of λ decreases as B PM increases. The decrease in λ is found to be linearly dependent on increasing B PM . The collar field for which flux-creep extrapolates to zero is found to be comparable to the maximum trappable field of the HTS bulk, B T, max . The properties of the dependence of λ on the HTS peak field, B T, max, the PM field, B PM, and the creep rate λ 0 with B PM = 0 permit the reduced creep rate in these experiments to be predicted by a universal equation.