  Ni-substitution effects on the superconductivity and Cu-spin correlation have
been investigated in La2-xSrxCu1-yNiyO4 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
CuO2 plane to the same degree as Zn, being discussed in relation to the
so-called dynamical stripe correlations of spins and holes.
