Temperature dependence of vortex flux pinning with γ-irradiation in polycrystalline Tl-2223
J Shobaki; M K Hasan; K Khasawinh; B A Albiss; Saleh Obeidat; I A Al-Omari
Журнал:
Superconductor Science and Technology
Дата:
2000-07-01
Аннотация:
Hysteresis loop measurements of superconducting polycrystalline samples of Tl-2223 were carried out at various temperatures. Using the magnetization remanence (M<sub>R</sub>) as measurement of the maximum vortex flux pinning at each temperature, our results reveal that the vortex flux pinning forces show two distinct behaviours of M<sub>R</sub> with temperature, a linear behaviour with t at high temperatures and an exponential behaviour with t<sup>β</sup> at low temperatures, where t = (1-T/T<sub>c</sub>) and β is constant of order 8. The effect of γ-irradiation shows six-fold enhancement in the vortex pinning over all temperatures up to T<sub>c</sub>. This increase in the pinning forces is attributed to the induced defects introduced by the γ-irradiation. The same enhancement in the pinning forces at all temperatures implies constant defects induced by γ-irradiation.
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