Effect of Zn substitution for Cu on Ca2-xNaxCuO2Cl2Ca2-xNaxCuO2Cl2 near the hole concentration of 18 per Cu

A weakening of superconductivity upon substitution of Cu by Zn (0.5–1%) is observed in a high-TcTc cuprate, Ca2-xNaxCuO2Cl2Ca2-xNaxCuO2Cl2, near the hole concentration of 18 per Cu. The superconducting transition temperature and its volume fraction, estimated by magnetic susceptibility, exhibit a sizable anomaly for x=0.12–0.14x=0.12–0.14, where the slowing down of Cu spin fluctuations below 5 K is demonstrated by muon spin relaxation experiments. These observations are in close resemblance to other typical cuprates including YBa2Cu3O7-δYBa2Cu3O7-δ, and Bi2Sr2Ca1-xYxCu2O8+δBi2Sr2Ca1-xYxCu2O8+δ, providing further evidence that Zn-induced “stripe” correlation is a universal feature of high-TcTc cuprate superconductors common to that of La2-xAxCuO4La2-xAxCuO4 (A=BaA=Ba, Sr).