Chalcogenide glass-ceramics for second harmonic generation

International audiencePermanent second harmonic generation (SHG) in chalcogenide based glass-ceramics containing highly nonlinear micro-crystals (crystalline particle size≈2-4 μm) has been demonstrated. In order to investigate whether a controlled crystallisation is an efficient way for improving the SH temporal stability and SH signal intensity of chalcogenide glasses, the Ge23Sb12S65 composition was chosen for its stability against crystallisation and atmospheric corrosion. Different amounts of metallic cadmium were introduced to promote CdS crystallite formation. Glass-ceramics with volume crystallisation were obtained by heat treating the glass samples at different temperatures from 370°C to 400°C and for different durations. The second order nonlinear signals were measured by using Maker fringes experiment. The first results indicate a nonlinearity in chalcogenide glass-ceramics approximately one hundred times lower than in α-quartz