B. Vonhedt et al., FLUX-PINNING IN BI2SR2CA1CU2O8-CRYSTALS WITH SUBSTITUTION OF FE, NI AND ZN(DELTA SINGLE), Physica. B, Condensed matter, 194, 1994, pp. 1905-1906
We report magnetic measurements on Bi2Sr2Ca1(Cu1-xMx)2O8+delta single
crystals with substitution of Fe, Ni, Zn for Cu. We find that the crit
ical current density is suppressed by about a factor of 2 by doping wi
th only 0.5 at.%. Similary the London penetration depth derived from t
he reversible magnetization is increasing definitely in the crystals w
ith low doping concentrations.