Preparation and Optical Nonlinear Property of Sol–Gel‐Derived Cu─SiO 2 Thin Films

Cu‐metal‐doped glass films having a Cu:Si atomic ratio of 0.05 ± 0.002 were successfully prepared by a sol‐gel method using a dipping technique. The appearance of surface plasmon of Cu metal at about 570 nm was observed after heat treatment at or above 700°C. The third‐order nonlinear susceptibility (x 3 ) was as high as 5.0 × 10 –8 esu at 570 nm.