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Thermally Activated Flux Motion in 2223 Phase High Temperature Superconductors
CHEN Jun, LI Gang, LI Chuanyi, FENG Qingrong, ZHANG Han, FENG Xiaoqi, ZHU Xing, YIN Daole
Chin. Phys. Lett. 1992, 9 (4):
206-208
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Isothermal V-I characteristics of Bi1.8Pb0.2Sr2Ca2Cu3Oy high temperature superconductors (HTSCs) have been systematically studied. Below the irre-versibility temperature Tr(H), two important features were observed: 1) Both positive and negative curvatures can coexist in the same isothermal V-I curve, so it is different from the scaling behavior V∝exp(-(J0/J)μ). 2) The activa-ion volume of flux motion is found temperature dependent as (1=T/Tr(H))-2v with v about 0.5. This behavior supports the existence of a two-dimensional secondary phase transition below Hc2(T) in this Bi-based HTSCs.
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15 articles
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