On the substitution of Zn for Cu atoms in high‐Tc superconductors: EPR measurements of La1.82Sr0.18(Cu1−xZnx)O4

EPR measurements of La1.82Sr0.18(Cu1−xZnx)O4 compounds reveal that Zn doping induces formation of localized magnetic moments which, as has been found here, sit on Cu ions. At Zn concentration of 1 atomic percent, the quantity of these magnetic moments is close to the amount of substituted ions. This result is important for verifying diverse microscopic mechanisms of high‐Tc superconductivity.