Similarity between Ni and Zn impurity effects on the superconductivity and Cu-spin correlation in La_(2-x)Sr_xCu_(1-y)Ni_yO_4 high-T_c cuprates: A comparison based on the hole trapping by Ni

摘要

Ni-substitution effects on the superconductivity and Cu-spin correlation have been investigated in La_(2-x)Sr_xCu_(1-y)Ni_yO_4 from the electrical resistivity and muon spin relaxation measurements, taking into account the hole trapping by Ni recently suggested. It has been found that the Ni substitution suppresses the superconductivity, induces the localization of holes, and develops the Cu-spin correlation to the same degree as the Zn substitution. These suggest that Ni with a trapped hole tends to give rise to potential scattering of holes in the CuO_2 plane to the same degree as Zn, being discussed in relation to the so-called dynamical stripe correlations of spins and holes.