학술논문
Effect of permanent-magnet irregularities in levitation force measurements.
Document Type
Conference
Author
Source
Conference: 2nd International Workshop on the Processing and Applications of Superconducting (RE)BCO Large Grain Materials, Morioka (JP), 10/20/1999--10/22/1999; Other Information: PBD: 14 Oct 1999
Subject
Language
English
Abstract
In the measurement of the levitation force between a vertically magnetized permanent magnet (PM) and a bulk high-temperature superconductor (HTS), PM domains with horizontal components of magnetization are shown to produce a nonnegligible contribution to the levitation force in most systems. Such domains are typically found in all PMs, even in those that exhibit zero net horizontal magnetic moment. Extension of this analysis leads to an HTS analog of Earnshaw's theorem, in which at the field-cooling position the vertical stiffness is equal to the sum of the horizontal stiffnesses, independent of angular distribution of magnetic moments within the PM.