D. Darminto, M. Diantoro, I.M. Sutjahja, A.A. Nugroho, W. Loeksmanto, M.O. Tjia
The oxygen doped and Pb-substituted single crystalline Bi2Sr2CaCu2O8+δ samples having Tc,on and anisotropy (γ2) ranging respectively from 65 to 93 K and from 773 to 49,715 have been studied in the basis of magneto-resistance and magnetization data. It is found that the lowering of anisotropy due to higher oxygen content or Pb substitution is responsible for the reduction of magnetic field-induced transitional broadening and a shift of Hirr(T) and Hg(T) to higher temperatures and magnetic field. Meanwhile, the increasing disorder manifested by decreasing Tc also leads to the extended range of appearance for the second magnetization peak (SMP) and enlarged critical glassy region. It is shown that decreasing anisotropy does not necessarily lead to the lowering of Tc in contrast to the monotonic dependence of Tc on the disorder measured in the temperature range of SMP effect. Additionally, a remarkable monotonic correlation between Tc and the glassy exponent s has been established. © 2002 Elsevier Science B.V. All rights reserved.
Department of Physics, Faculty of Mathematics and Science, Sepuluh Nopember Institute of Technology, Sukolilo, Surabaya 60111, Indonesia; Department of Physics, Bandung Institute of Technology, Bandung 40132, Jl. Ganesa 10, Indonesia; Department of Physics, Universitas Negeri Malang, Malang 65145, Jl. Surabaya 6, Indonesia; Van der Waals-Zeeman Institute, University of Amsterdam, 1018 XE Amsterdam, Valckenierstraat 65, Netherlands
