ISSN:
0392-6737
Keywords:
Flux pinning
;
flux motion
;
fluxon-defect interactions
;
Conference proceedings
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Summary Measurements of fundamental and higher harmonics of a.c. susceptibility on polycrystalline high-T c superconductors were carried out using a new method, involving a 2-channel dynamic analyser, allowing 20 harmonics in phase and out of phase to be measured at the same time. The critical-state model, used for describing the higher-harmonics dependence on temperature at fixed d.c. and a.c. magnetic fields, did not explain the experimental results. A frequency analysis indeed suggested that an effect of the fluxon dynamics takes place. Simple considerations lead to the conclusion that really Thermally Activated Flux Flow (TAFF), Flux Creep (FC) and Flux Flow (FF) would have a big role in determining the higher harmonics of a.c. susceptibility. Measurements on low-T c superconductors showed the occurrence of the same effect.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02462194
