Influence of the Nonmagnetic Impurity on the Spin Density State of High-T_c Cuprate Oxides

This letter deals with the suppressive effect of the nonmagnetic impurity, doped into the parent compound of the high-T_c superconductor, on the spin density wave (SDW) state. Taking into account the van Hove singularity in the Fermi surface of the two-dimensional square lattice, our results indicate that the nonmagnetic impurity can lead to sharp reduction of the SDW order, which is in qualitative agreement with the experimental reports.