Effect of magnetic and nonmagnetic impurities (Ni, Zn) substitution for Cu inBi2(SrCa)2+n

Abstract

We have measured the change in the resistive T c of Bi 2 (SrCa) 2ϩn (Cu 1Ϫx M x ) 1ϩn O y whiskers due to substitution of M ϭ Ni ͑magnetic͒ or M ϭ Zn ͑nonmagnetic͒ for Cu. These whisker crystals show resistance drops for both the 2212 and 2223 (nϭ1,2) phases, with transition widths ͑10-90 %͒ of 1 K. We checked the effect of oxygenation at several values of x, and found that T c is maximum for the y obtained by growing and annealing in 1 atm of O 2 . We observed a linear depression of T c for both 2212 and 2223 phases with DϭdT c /dxϷϪ800 K for both Ni and Zn. This is in contrast with YBCO in which D Zn Ϸ3D Ni .

Interplay of magnetism and high-Tc superconductivity at individual Ni impurity atoms in Bi2Sr2CaCu2O8+δ

“…The similarity of these phase shifts imply that phenomena dependent on scattering should be quite similar in Ni-and Zndoped samples. In fact, using these parameters in an Abrikosov-Gorkov model 1 (and ignoring Ni's magnetic potential) we calculate that T C would be suppressed only about 20% faster by Zn than by Ni, certainly within the range of experimental observations 21,22 .…”

Superconductivity suppression of Ba0.5K0.5Fe2−Li1, Guo2, Zhang3 et al. 2012Phys. Rev. B8771083View full textAdd to dashboardCite

“…8 16,22-24 . A few at.% of the Zn acts as a strong scattering center and remarkably depresses SC due to the d-wave anisotropic gap for cuprates [16][17][18][19][20][21][22][23][24] . Since the doped Zn often plays a crucial role of pairing symmetry determination of previous superconductors, we may expect that it works with the Fe-based superconductor as well.…”

“…23,24 , it is uncertain that whether Zn has been successfully substituted into the Fe-site for previous polycrystals synthesized in ambient-pressure. Our recent studies indeed showed that more than 2 at.% of Zn were hardly doped into the n-type Ba(Fe,Co) 2 As 2 superconductor at ambient pressure condition 29 .…”

Effect of Al Substitution on Structural and Electrical Properties of Bi1.6Pb0.4Sr2CaCu2−x M x O8+δ Superconducting Ceramics

“…These kinds of doping have been made in order to control the charge carrier concentration in these planes and consequently to control the superconducting properties. The results obtained in Bi2212 [11][12][13] by doping with Fe, Zn, Ni or Co, have shown that the situation is a little more complex. The sample shows, in its normal state, a behavior interpreted by some authors as a pseudo gap and by others as a quantum critical point [14][15][16].…”