Glass, optical applications waveguides

Heavy-metal fluoride glasses hold a large potential for optical applications in the middle infrared, namely in fiber form as optical waveguides, fiber lasers and sensors, but also in bulk form as prisms, lenses, light pipes or optieal windows. This potential has stimulated extensive research into their structure and properties, but present knowledge is still largely incomplete due to unusual structural characteristics such as... 

The poled polymer approach is state-of-the-art in terms of the application of polymers to electro-optic devices such as modulators and waveguides. Chromophore-bound polymers for second-order nonlinear optical applications with glass transition temperatures greater than 320°C have been reported (5). However, the electro-optic coefficients are modest, typically less than 10 pm/V at 1.3 im. Part of the poling problem is caused by electrical conductivity at high poling temperatures, which reduces the poling field, or worse, sometimes causes dielectric breakdown. 

Four different sol-gel routes can be used to prepare various kinds of sulfide materials. Sol-gel synthesis of sulfides usually follows colloidal chemical processing, except route A. It is very important to control the sizes of colloidal particles. As-S and Ge-S glass films could be prepared by sol-gel processing for planar waveguides, for IR optical applications. The sol-gel synthesis of multicomponent sulfide glasses needs further study, perhaps based on the Ge-S system. Route D can also be used for synthesis of multicomponent sulfides. 

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