Ion exchange in glass: A mature technology for photonic devices

Ion exchange processes in glass have been studied since several decades, and have demonstrated themselves as one of the most convenient technologies to produce integrated optical components and devices. Ion-exchanged waveguides are attractive candidates for photonic components because they exhibit low insertion losses, thanks also to the capability of very good matching to the modal field of an optical fiber, and their fabrication costs are very low in batch production. A brief overview of the main processes and demonstrated applications is presented here.