Magnetic field and temperature dependence of intergranular activation energy in polycrystalline HgBa2Ca2Cu3O8+delta and (Tl,Pb,Bi)(Ba,Sr)(2)Ca2Cu3Oy superconductors

摘要

The ac susceptibilities of polycrystalline HgBa2Ca2Cu3O8+delta and (Tl,Pb,Bi)(Ba,Sr)(2)Ca2Cu3Oy samples were measured as a function of temperature, magnetic field and frequency. Activation energy of both samples, obtained from Arrhenius plot for the frequency f and the maximum temperature T-p in imaginary part chi(n) of ac susceptibility, approximated by U(H,T) approximate to A(1-T/T-c)H-alpha for temperature and field. The maximum field H-p in imaginary part chi(n) of both samples showed the power-law dependence of (1 -T/T-c)(n) for temperature range near T-c. (C) 1998 Elsevier Science B.V. [References: 16]