On the mechanism of non-linear optical attenuation at 1.3–1.5 μm in arsenic sulfide and tellurium oxide glasses

The mechanism of optical non-resonant non-linear refraction and absorption/attenuation in glasses at 1.3–1.5 μm is of interest for efficient all-optical switching in optical fibre telecommunications. We discuss the mechanism of non-resonant non-linear attenuation (loss) at 1.3–1.5 μm in glasses with the largest linear refractive indices, such as As2S3- and TeO2-based glasses. These glasses are transparent and possess the largest non-resonant non-linear refraction at 1.3–1.5 μm to date (up to 10−14 cm2/W), allow single-mode fiberization and therefore are suitable for all-optical fibre switching. We show that with a single beam Z-scan technique we identify the contribution of small-angle non-linear scattering to the total non-linear attenuation at 1.3–1.5 μm. We show that small-angle non-linear scattering does contribute to the non-linear attenuation at such irradiances at which non-linear absorption is not present yet.